Photosensor

ABSTRACT

A photosensor includes a sensor module in which emitter and receiver leads protrude from a circuit-encapsulating portion in a direction intersecting with a direction in which an external connecting terminal extends. The photosensor includes a light emitter, a light receiver, a circuit-encapsulating portion, a connecting terminal, first and second emitter leads, and first and second receiver leads. When the connecting terminal extends in a first direction, and a first plane is parallel to the first direction, the first and second emitter leads protrude from the circuit-encapsulating portion in a direction parallel to the first plane and intersecting with the first direction, and extend opposite to the first direction. The first and second receiver leads protrude from the circuit-encapsulating portion in the direction parallel to the first plane and intersecting with the first direction and opposite to a direction in which the first and second emitter leads protrude, and extend opposite to the first direction. The first and second emitter leads and the first and second receiver leads are deformed to allow the light receiver and the light emitter to face each other.

FIELD

The present invention relates to a photosensor.

BACKGROUND

A photoelectric sensor known in the art is described in PatentLiterature 1. The photosensor includes an emitter lead connected to alight emitter, a receiver lead connected to a light receiver, acircuit-encapsulating portion encapsulating an integrated circuit, andconnecting terminals connected to external terminals. In thisphotosensor, the emitter lead and the receiver lead protrude from thecircuit-encapsulating portion in a direction opposite to the directionin which the connecting terminals extend.

CITATION LIST Patent Literature

Patent Literature 1: Japanese Unexamined Patent Application PublicationNo. 11-145505

SUMMARY Technical Problem

Some designs of photosensors may include a receiver lead that protrudesfrom a circuit-encapsulating portion in a direction intersecting withthe direction in which external connecting terminals extend. However,sensor modules known in the art have yet to achieve such designs inwhich the emitter and receiver leads protrude from thecircuit-encapsulating portion in the direction intersecting with thedirection in which the external connecting terminals extend.

To respond to this situation, it is an object of the present inventionto provide a photosensor including a sensor module in which emitter andreceiver leads protrude from a circuit-encapsulating portion in adirection intersecting with a direction in which external connectingterminals extend.

Solution to Problem

A first aspect of the invention provides a photosensor including a lightemitter, a light receiver, a circuit-encapsulating portion, a connectingterminal, a first emitter lead, a second emitter lead, a first receiverlead, and a second receiver lead. The light receiver receives light fromthe light emitter and outputs a light receiving signal. Thecircuit-encapsulating portion encapsulates an integrated circuit thatprocesses the light receiving signal. The connecting terminal protrudesfrom the circuit-encapsulating portion and connects to an externalterminal. The first emitter lead and the second emitter lead are flatplates. The emitter leads connect the light emitter and thecircuit-encapsulating portion. The first receiver lead and the secondreceiver lead are flat plates. The receiver leads connect the lightreceiver and the circuit-encapsulating portion. When a direction inwhich the connecting terminal extends is a first direction, and a planeparallel to the first direction is a first plane, the first emitter leadand the second emitter lead protrude from the circuit-encapsulatingportion in a direction parallel to the first plane and intersecting withthe first direction, and extend in a direction opposite to the firstdirection. The first receiver lead and the second receiver lead protrudefrom the circuit-encapsulating portion in a direction parallel to thefirst plane and intersecting with the first direction and opposite to adirection in which the first emitter lead and the second emitter leadprotrude, and extend in the direction opposite to the first direction.The first emitter lead and the second emitter lead, and the firstreceiver lead and the second receiver lead are deformed to allow thelight receiver and the light emitter to face each other. This achievesthe sensor module structure in which the emitter and receiver leadsprotrude in the direction intersecting with the direction in which theconnecting terminal extends.

The first emitter lead and the second emitter lead may be bent along afirst bending line that is parallel to a second direction perpendicularto an optical axis of light. The first receiver lead and the secondreceiver lead may be bent along a second bending line that is parallelto the second direction. The simple processing allows the light emitterand the light receiver to face each other, and enables easy fabricationof the photosensor.

When the first emitter lead and the second emitter lead are unfolded ina plane without bending along the first bending line, the unfolded firstemitter lead and the unfolded second emitter lead may extend across thefirst bending line. When the first receiver lead and the second receiverlead are unfolded in a plane without bending along the second bendingline, the unfolded first receiver lead and the unfolded second receiverlead may extend across the second bending line. In this structure, thefirst emitter lead and the second emitter lead occupy both sides of thefirst bending line. Such leads provide areas to be pressed in theprocess of bending, and thus the first emitter lead and the secondemitter lead can be bent easily. Likewise, the first receiver lead andthe second receiver lead also occupy both sides of the second bendingline and provide areas to be pressed in the process of bending, and thusthe first and second receiver leads can be bent easily.

The first emitter lead may include a first emitter lead portion, asecond emitter lead portion, a third emitter lead portion, and a fourthemitter lead portion. The first emitter lead portion protrudes from thecircuit-encapsulating portion in a direction parallel to the first planeand intersecting with the first direction, and extends in a directionopposite to the first direction. The second emitter lead portion extendsfrom the first emitter lead portion in one of an inward direction or anoutward direction along an optical axis of the light. The third emitterlead portion is connected to the second emitter lead portion. The fourthemitter lead portion extends from the third emitter lead portion in theother one of the inward direction or the outward direction along theoptical axis. The fourth emitter lead portion may include a firstbending portion that is bent along the first bending line. The firstreceiver lead may include a first receiver lead portion, a secondreceiver lead portion, a third receiver lead portion, and a fourthreceiver lead portion. The first receiver lead portion protrudes fromthe circuit-encapsulating portion in a direction parallel to the firstplane and intersecting with the first direction, and extends in adirection opposite to a direction in which the first emitter lead andthe second emitter lead protrude. The second receiver lead portionextends from the first receiver lead portion in one of an inwarddirection or an outward direction along the optical axis. The thirdreceiver lead portion is connected to the second receiver lead portion.The fourth receiver lead portion extends from the third receiver leadportion in the other one of the inward direction or the outwarddirection. The fourth receiver lead portion includes a second bendingportion bent along the second bending line. The first emitter lead caninclude the bending portion that allows the light emitter and the lightreceiver to face each other, without widening the first emitter lead inthe direction intersecting with the first direction. Likewise, the firstreceiver lead can include the bending portion that allows the lightemitter and the light receiver to face each other, without widening thefirst receiver lead. This structure increases the degree of freedom indesigning the shape of the photosensor, and also uses less material forthe leads.

An inner end of the second emitter lead portion may be located moreinward than an outer end of the fourth emitter lead portion in adirection along the optical axis. An inner end of the fourth emitterlead portion may be located more inward than an outer end of the secondemitter lead portion in the optical axis direction. An inner end of thesecond receiver lead portion may be located more inward than an outerend of the fourth receiver lead portion in the optical axis direction.An inner end of the fourth receiver lead portion may be located moreinward than an outer end of the second receiver lead portion in theoptical axis direction. This structure allows the fourth emitter leadportion and the fourth receiver lead portion to be long, and allows easybending of the leads to arrange the light emitter and the light receiverfacing each other.

The second emitter lead portion may extend inward from the first emitterlead portion in a direction along the optical axis. The fourth emitterlead portion may extend outward from the third emitter lead portion inthe optical axis direction. The second receiver lead portion may extendinward from the first receiver lead portion in the optical axisdirection. The fourth receiver lead portion may extend outward from thethird receiver lead portion in the optical axis direction. Thisstructure allows the fourth emitter lead portion and the fourth receiverlead portion to be long without widening the emitter lead and thereceiver lead in a direction intersecting with the first direction, andallows easy bending for arranging the light emitter and the lightreceiver facing each other.

The second emitter lead may be located more inward than the firstemitter lead in the optical axis direction. The second receiver lead maybe located more inward than the first receiver lead in the optical axisdirection. A distance between the second emitter lead and the thirdemitter lead portion in the optical axis direction may be smaller than adistance between the second emitter lead and the first emitter leadportion in the optical axis direction. A distance between the secondreceiver lead and the third receiver lead portion in the optical axisdirection may be smaller than a distance between the second receiverlead and the first receiver lead portion in the optical axis direction.This structure allows the fourth emitter lead portion and the fourthreceiver lead portion to be longer, and allows easier bending forarranging the light emitter and the light receiver facing each other.

The second emitter lead may include an inclined light emitting portionthat is inclined to increase a distance thereof to the first emitterlead portion in the optical axis direction. The second receiver lead mayinclude an inclined light receiving portion that is inclined to increasea distance thereof to the first receiver lead portion in the opticalaxis direction. This increases the distance for insulation between thefirst emitter lead and the second emitter lead, and achieves higherinsulation between them.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a photosensor according to one embodiment.

FIG. 2 is a top view of the photosensor according to the embodiment.

FIG. 3 is an exploded perspective view of the photosensor according tothe embodiment.

FIG. 4 is a cross-sectional view of the photosensor taken along lineIV-IV in FIG. 2.

FIG. 5 is a cross-sectional view of the photosensor taken along line V-Vin FIG. 1.

FIG. 6 is a plan view of a sensor module according to the embodiment.

FIG. 7 is a plan view of a primary molded piece of the sensor moduleaccording to the embodiment.

FIG. 8 is a plan view of the detailed internal circuitry covered byresin in the sensor module shown in FIG. 6.

FIG. 9 is an enlarged view of an area including a protrusion.

FIG. 10 is a flowchart showing a method for manufacturing a sensormodule according to the embodiment.

FIG. 11 is a flowchart showing another method for manufacturing a sensormodule according to the embodiment.

FIGS. 12A and 12B are side views of the sensor module shown in FIG. 7.

FIG. 13 is an enlarged view of a plurality of connecting terminals andtheir surrounding area.

FIG. 14 is an enlarged view of an area including a first inner terminaland a third inner terminal.

FIG. 15A is a diagram showing a first inner terminal and a third innerterminal according to modifications of the embodiment.

FIG. 15B is a diagram showing a first inner terminal and a third innerterminal according to modifications of the embodiment.

FIG. 16 is a plan view of a sensor module according to a modification.

FIG. 17 is a plan view of a primary molded piece of the sensor moduleaccording to the modification.

FIG. 18 is a side view of the sensor module including emitter andreceiver leads bent into an L-shape as viewed in the optical axisdirection.

FIGS. 19A to 19D are detailed views of a subcase.

FIG. 20 is a front view of a photosensor according to anotherembodiment.

FIG. 21 is a top view of the photosensor according to the otherembodiment.

FIG. 22 is an exploded perspective view of the photosensor according tothe other embodiment.

FIG. 23 is a cross-sectional view of the photosensor taken along lineXXIII-XXIII in FIG. 21.

DETAILED DESCRIPTION

An embodiment of the present invention will now be described withreference to the drawings. In the drawings referred to herein, the samenumerals indicate the same or the corresponding components.

FIG. 1 is a front view of a photosensor 1. FIG. 2 is a top view of thephotosensor 1. FIG. 3 is an exploded perspective view of the photosensor1. In FIG. 3, the photosensor 1 includes a sensor module 5, a case 60, asubcase 80, and a bottom plate 98.

As shown in FIG. 1, the case 60 includes a case body 61, an emitter casesection 62, and a receiver case section 63. FIG. 4 is a cross-sectionalview of the photosensor taken along line IV-IV in FIG. 2. In FIG. 4, thesensor module 5 is not sectioned. Referring to FIG. 4, the case body 61accommodates a circuit-encapsulating portion 90, which will be describedbelow. The emitter case section 62 accommodates a light emitter 10, afirst emitter lead 20, and a second emitter lead 22, which will bedescribed below. The receiver case section 63 accommodates a lightreceiver 15, a first receiver lead 24, and a second receiver lead 26,which will be described below. The emitter case section 62 and thereceiver case section 63 extend upward from the case body 61. FIG. 5 isa cross-sectional view of the photosensor taken along line V-V inFIG. 1. Referring to FIG. 5, the emitter case section 62 includes anemitter slit 66 on its surface facing the receiver case section 63. Thereceiver case section 63 includes a receiver slit 67 on its surfacefacing the emitter case section 62.

The present embodiment defines the directions as described below unlessotherwise specified. The direction from the emitter slit 66 toward thereceiver slit 67 is the right, and the direction opposite to thisdirection is the left. In the figures, the positive direction of X axisis the right. The right and the left correspond to the direction of anoptical axis Ax of the light emitted from the light emitter 10 towardthe light receiver 15 described below. The direction from the connectingterminals 50 toward the emitter and receiver case sections 62 and 63 isan upward direction, and the direction opposite to this direction is adownward direction. In the figures, the positive direction of Y axis isthe upward direction. The direction from the center of the photosensor 1toward the surface of the case 60 including an indicator lamp window 68is the front, and the direction opposite to this direction is the back.In the figures, the positive direction of Z axis is the front.

The emitter case section 62 and the receiver case section 63 face eachother. The photosensor 1 includes the pair of emitter and receiver slits66 and 67 facing each other on an upper portion of the case 60. Theemitter case section 62 and the receiver case section 63 are spaced fromeach other in the direction of the optical axis Ax (X-axis direction).As shown in FIGS. 1 and 2, the case 60 includes mounting holes 69 a, 69b, 69 c, and 69 d, which are formed through the case 60 in directionsperpendicular to the direction in which the emitter and receiver slits66 and 67 face each other (Y-axis and X-axis directions in FIG. 1).

In the photosensor 1, the sensor module 5 includes a plurality ofconnecting terminals 50, which protrude outward from the bottom plate98. As shown in FIG. 1, the case 60 includes the square indicator lampwindow 68 on its front surface. Through the indicator lamp window 68, anoperator can visually check an operation indicator lamp (hereafterreferred to as an operation indicator 92). The operation indicator lampilluminates under a predetermined condition, or specifically when alight receiving signal from the light receiver 15 exceeds apredetermined threshold or when the signal is below the threshold. Thecondition for turning on the operation indicator lamp will be describedbelow.

As shown in FIG. 3, the subcase 80 and the sensor module 5 are placedinto the case 60 in this order. The base plate 98, which includes holes99 through which the connecting terminals 50 are placed, is thenattached to the bottom of the case 60.

FIG. 6 is a plan view of the sensor module 5. FIG. 7 is a plan view of aprimary molded piece of the sensor module 5. In other words, FIG. 7 isan unfolded view of the sensor module 5 in FIG. 6. The sensor module 5unfolded in a plane shown in FIG. 7 is hereafter referred to as a sensormodule 4. FIG. 8 is a plan view of the detailed internal circuitrycovered by resin in the sensor module 4 shown in FIG. 6.

Referring to FIG. 6, the sensor module 5 includes the light emitter 10,the light receiver 15, the first emitter lead 20, the second emitterlead 22, the first receiver lead 24, the second receiver lead 26, theintegrated circuit 41, the circuit-encapsulating portion 90, and theconnecting terminals 50. The first emitter lead 20, the second emitterlead 22, the first receiver lead 24, the second receiver lead 26, andthe connecting terminals 50 are hereafter collectively referred to as aleadframe 8. The sensor module may be referred to as a photosensorcomponent.

The leadframe 8 includes conductive flat plates. In other words, thefirst emitter lead 20, the second emitter lead 22, the first receiverlead 24, the second receiver lead 26, and the connecting terminals 50are the flat plates.

The light emitter 10 includes an emitter element 11 and an emitterencapsulating portion 12. The emitter encapsulating portion 12 includesan emitter base 13 and an emitter lens 14. In one example, the emitterelement 11 is a light-emitting diode, although it may be anotherelement. The emitter encapsulating portion 12 encapsulates the emitterelement 11 with resin. The emitter base 13 covers the emitter element11. The emitter lens 14 has a curved surface, and protrudes from theemitter base 13. The emitter lens 14 is circular as viewed in thedirection of light being emitted. The emitter lens 14 collimates thelight emitted from the emitter element 11, and thus prevents the lightfrom the emitter element 11 from diverging.

The light receiver 15 receives light from the light emitter 10, andoutputs a light receiving signal. The light receiver 15 includes areceiver element 16 and a receiver encapsulating portion 17. Thereceiver encapsulating portion 17 includes a receiver base 18 and areceiver lens 19. In one example, the receiver element 16 is aphototransistor, although it may be another element. The receiverelement 16 and the emitter element 11 are arranged to face each other.More specifically, the photosensor 1 according to this embodiment is atransmissive photosensor that detects whether the receiver element 16can directly receive light emitted from the emitter element 11. Thereceiver encapsulating portion 17 encapsulates the receiver element 16with resin. The receiver base 18 covers the receiver element 16. Theemitter lens 19 has a curved surface, and protrudes from the emitterbase 18. The emitter lens 19 is circular as viewed in the direction oflight being received. The emitter lens 14 focuses light from the emitterelement 11 onto the receiver element 16.

Referring to FIG. 8, the emitter element 11 is mounted on the firstemitter lead 20. In other words, the emitter element 11 is mounted onthe leadframe 8. The receiver element 16 is mounted on the secondreceiver lead 26. In other words, the receiver element 16 is mounted onthe leadframe 8.

The integrated circuit 41 is electrically connected to the emitterelement 11 and the receiver element 16. The integrated circuit 41 ismounted on a main lead 30, which is a part of the leadframe 8. Theintegrated circuit 41 is fixed to the leadframe 8 by, for example, diebonding, and is wired by wire bonding. In this manner, the integratedcircuit 41 is mounted onto the leadframe 8. The leadframe 8 thusincludes the main lead 30, and is connected to the integrated circuit41. The main lead 30, which is to be encapsulated in thecircuit-encapsulating portion described below, is a part of theleadframe 8 excluding the leads that function as the connectingterminals 50. The leads that function as the connecting terminals 50will be described below.

The first emitter lead 20 and the second emitter lead 22 connect thelight emitter 10 and the circuit-encapsulating portion 90. Morespecifically, the first emitter lead 20 connects the emitter element 11and the main lead 30. The second emitter lead 22 and a wire W11 connectthe emitter element 11 and the main lead 30. The main lead 30 isconnected to the integrated circuit 41 to connect the light emitter 10to the integrated circuit 41 with the first and second emitter leads 20and 22. The downward direction (the direction in which the connectingterminals 50 extend, or the negative direction of Y axis) is referred toas a first direction. A plane parallel to the first direction isreferred to as a first plane. The first plane is, for example, a planedefined by the surfaces of the connecting terminals 50 (XY plane). Thefirst emitter lead 20 and the second emitter lead 22 extend from thecircuit-encapsulating portion 90 in a direction parallel to the firstplane and intersecting with the first direction (to the left, or in thenegative direction of X axis). The first emitter lead 20 and the secondemitter lead 22 extend in a direction opposite to the first direction(the positive direction of Y axis).

The first receiver lead 24 and the second receiver lead 26 connect thelight receiver 15 and the circuit-encapsulating portion 90. Morespecifically, the first receiver lead 24 and a wire W12 connect thereceiver element 16 and the main lead 30. The main lead 30 is connectedto the integrated circuit 41 to connect the light receiver 15 to theintegrated circuit 41 with the first and second receiver leads 24 and26. As shown in FIG. 6, a plane perpendicular to the optical axis Ax oflight emitted from the light emitter 10 toward the light receiver 15 andincluding the midpoint between the light emitter 10 and the lightreceiver 15 is referred to as a plane C1. In this case, the firstreceiver lead 24 and the second receiver lead 26 protrude from thecircuit-encapsulating portion 90 in a direction parallel to the firstplane and intersecting with the first direction. The first receiver lead24 and the second receiver lead 26 extend in the direction opposite tothe direction in which the first emitter lead 20 and the second emitterlead 22 extend (to the right, or in the positive direction of X axis).When, for example, the circuit-encapsulating portion 90 is a rectangularprism, the first receiver lead 24 and the second receiver lead 26protrude from the surface of the circuit-encapsulating portion 90 facingthe surface from which the first emitter lead 20 and the second emitterlead 22 protrude. These leads may protrude at any angles. The first andsecond receiver leads 24 and 26 protrude from the circuit-encapsulatingportion 90 by a predetermined length and then bend, and extend in thedirection opposite to the first direction (or the positive direction ofY axis).

As shown in FIG. 6, the first emitter lead 20 and the second emitterlead 22 and the first receiver lead 24 and the second receiver lead 26in the sensor module 5 are bent and deformed to allow the light emitter10 and the light receiver 15 to face each other. The light receiver 15is arranged to face the light emitter 10. In the example of FIG. 6, eachof the first and second emitter leads 20 and 22 and the first and secondreceiver leads 24 and 26 is bent at a single point. Alternatively, theleads may be bent at a plurality of points, or may be twisted. Thespecific shapes and the bending characteristics of the first and secondemitter leads 20 and 22 and the first and second receiver leads 24 and26 will be described below.

The integrated circuit 41 includes, for example, an integrated circuit(IC) chip. The integrated circuit 41 applies a voltage to the gate of atransistor (not shown) connected to the emitter element 11 to allow acurrent to flow through the emitter element 11, which then emits light.Through this process, the integrated circuit 41 controls light emissionfrom the emitter element 11. The integrated circuit 41 includes acurrent-voltage converter circuit, an amplifier circuit, and an A/Dconverter circuit (not shown). The integrated circuit 41 converts aphotocurrent output from the receiver element 16 to a voltage, amplifiesthe voltage, and then determines the value of a light receiving signal,which is a digital value. The integrated circuit 41 also determineswhether the receiver element 16 has received light by comparing thesignal value with a predetermined threshold. This threshold is set basedon the light receiving signals measured in a first case in which anobject blocking light is detected between the light emitter 10 and thelight receiver 15 and a second case in which no such object is detectedbetween. The threshold allows the integrated circuit 41 to distinguishbetween the first case and the second case. The threshold is stored in,for example, an internal memory of the integrated circuit 41.

The sensor modules 4 and 5 each include a light emitting element 42,which illuminates the operation indicator 92. The integrated circuit 41is connected to the light emitting element 42 with the wire W1. Theintegrated circuit 41 controls the light emitting element 42 based on aresult of determination for light reception. The light emitting element42, which is for example a light-emitting diode, is mounted on the mainlead 30. In other words, the light emitting element 42 is mounted on theleadframe 8. The integrated circuit 41 and the light emitting element 42are hereafter collectively referred to as a circuit block 40. Theintegrated circuit 41 processes the light receiving signal transmittedfrom the light receiver 15. Either when the value of the light receivingsignal is not less than the threshold, or when the signal value is belowthe threshold, the integrated circuit 41 applies a control signal with apredetermined voltage to a transistor (not shown) connected to the lightemitting element 42 to turn on the light emitting element 42. The lightemitting element 42 indicates the operation of the photosensor 1, orspecifically the result of the processing performed by the integratedcircuit 41.

In response to a light receiving signal from the light receiver 15, theintegrated circuit 41 performs either the first processing or the secondprocessing described below.

-   First Processing: When the value of the light receiving signal is    not less than a predetermined threshold, the integrated circuit 41    outputs a control signal for turning on the light emitting element    42 (an ON signal, or for example a signal for outputting a power    supply voltage Vcc). When the value of the light receiving signal is    below the predetermined threshold, the integrated circuit 41 outputs    a control signal for turning off the light emitting element 42 (an    OFF signal, or for example a signal for outputting 0 V).-   Second Processing: When the value of the light receiving signal is    not less than a predetermined threshold, the integrated circuit 41    outputs a control signal for turning off the light emitting element    42 (an OFF signal). When the value of the light receiving signal is    below the predetermined threshold, the integrated circuit 41 outputs    a control signal for turning on the light emitting element 42 (an ON    signal).

Switching Terminal

The integrated circuit 41 switches between the first processing and thesecond processing in accordance with the voltage at a port P1. Thevoltage at the port P1 differs depending on whether a protrusion 46included in a power supply voltage wiring group 44 has been cut.Referring to FIG. 8, the power supply voltage wiring group 44 includeswires and leads for transmitting the power supply voltage Vcc to theport P1. The power supply voltage wiring group 44 includes wires W2, W3,and W4, the protrusion 46, and a first lead 32 and a second lead 34. Thefirst lead 32 and the second lead 34 are parts of the main lead 30. Inother words, the main lead 30 includes the first lead 32 and the secondlead 34. When the protrusion 46 is connected to the first lead 32 andthe second lead 34, the protrusion 46 and the first lead 32 and thesecond lead 34 form a single lead. In other words, the leadframe 8includes the protrusion 46, the first lead 32, and the second lead 34.

The power supply voltage Vcc is applied to a power supply connectingterminal 51, which is one of the connecting terminals 50. The wires W2and W3 connect the power supply connecting terminal 51 to the first lead32. The first lead 32 is connected to a port P2 of the integratedcircuit 41 with a wire W13. The protrusion 46 is connected to the firstlead 32 and extends out of the circuit-encapsulating portion 90. Theprotrusion 46 is connected to the second lead 34. The wire W4 connectsthe second lead 34 to the port P1 of the integrated circuit 41. When theprotrusion 46 remains connected, the port P1 receives the power supplyvoltage Vcc applied from the power supply connecting terminal 51 throughthe wires W2 and W3, the first lead 32, the protrusion 46, the secondlead 34, and the wire W4. When the protrusion 46 has been cut, thesecond lead 34, the wire W4, and the port P1 enter an electricallyfloating state (with no electrical connection). In this case, a voltageother than the power supply voltage Vcc (for example, 0 V) is applied tothe port P1. When the power supply voltage Vcc is applied to the portP1, the integrated circuit 41 performs one of the first processing orthe second processing described above. When a voltage other than thepower supply voltage Vcc is applied to the port P1, the integratedcircuit 41 performs the other one of the first processing or the secondprocessing. The figures other than FIG. 8 each show the module fromwhich the protrusion 46 has been removed.

FIG. 9 is an enlarged view of an area including the protrusion 46.Referring to FIG. 9, the protrusion 46 includes a first protrusion 464,a second protrusion 466, and an external connector 460. The firstprotrusion 464 connects to the first lead 32. The second protrusion 466connects to the second lead 34. The first protrusion 464 and the secondprotrusion 466 protrude at different positions of thecircuit-encapsulating portion 90. The external connector 460 connectsthe first protrusion 464 to the second protrusion 466. The externalconnector 460 extends from the first protrusion 464 in a directiondifferent from the direction in which the first protrusion 464protrudes. Likewise, the external connector 460 extends from the secondprotrusion 466 in a direction different from the direction in which thesecond protrusion 466 protrudes.

The first protrusion 464 and the first lead 32 may be collectivelyreferred to as a first leadframe. The second protrusion 466 and thesecond lead 34 may be collectively referred to as a second leadframe.The sensor module 5 is fixed in either a first state where the firstprotrusion 464 and the second protrusion 466 are electrically connected,or a second state where the first protrusion 464 and the secondprotrusion 466 are electrically isolated. The sensor module 5 fixed inthe first state performs one of the first processing or the secondprocessing described above. The sensor module 5 fixed in the secondstate performs the other one of the first processing or the secondprocessing.

The first protrusion 464 has a width D1 in the direction perpendicularto the direction in which the first protrusion 464 protrudes. The secondprotrusion 466 has a width D2 in the direction perpendicular to thedirection in which the second protrusion 466 protrudes. The firstprotrusion 464 and the second protrusion 466 are spaced from each otherby a distance D3, which is not less than the width D1 and not less thanthe width D2, at an end surface of the circuit-encapsulating portion 90from which the first and second protrusions 464 and 466 protrude. Thisstructure prevents the first lead 32 and the second 34 from coming incontact with each other with burrs that can form when the protrusion 46is cut and removed.

As shown in FIG. 8, the protrusion 46 is arranged between the firstemitter lead 20 and the second emitter lead 22 on the first plane (XYplane) described above.

The protrusion 46 may be arranged between the first receiver lead 24 andthe second receiver lead 26 on the first plane (XY plane). Thisarrangement reduces the likelihood that the protrusion 46 can come incontact with the case 60 when the sensor module 5 is encased, and thusprevents the protrusion 46 from being disconnected accidentally when thesensor module 5 is encased.

As described above with reference to FIG. 9, the first processing andthe second processing can be switched depending on whether theprotrusion 46 is cut. Alternatively, the external connector 460 may be aconductive member separate from the first protrusion 464 and the secondprotrusion 466. In this structure, the external connector 460 may beattached or detached to switch the processing of the sensor module 5between the first processing and the second processing. The externalconnector 460, which is a separate member from the first protrusion 464and the second protrusion 466, may be referred to as a connector chip.The connector chip is, for example, a rectangular member having a widthnot less than D3.

A method for manufacturing a sensor module using the protrusion 46 willnow be described. FIG. 10 is a flowchart showing a method ofmanufacturing the sensor module 4. In step S1, an intermediate componentfor a first photosensor is prepared. The first photosensor intermediatecomponent is a sensor module (a sensor component) including theprotrusion 46 shown in FIGS. 8 and 9 in the stage in which whether theprotrusion 46 is to be cut has yet to be determined. In one example, thefirst photosensor intermediate component is prepared in the mannerdescribed below. The emitter element 11, the receiver element 16, theintegrated circuit 41, and the light emitting element 42 are firstmounted onto the leadframe 8 by die bonding. The components are thenconnected to the leadframe by wire bonding. Subsequently, aresin-molding process is performed to form the light emitter 10, thelight receiver 15, and the circuit-encapsulating portion 90. Unnecessaryportions of the leadframe 8 are then removed. The primary molded pieceis released from the leadframe 8, and burrs on the molded piece areremoved.

After the processing in step 51 completes, the manufacturer determineswhether any part of the protrusion 46, which includes the firstprotrusion 464, the second protrusion 466, and the external connector460 of the first photosensor intermediate component, is to be cut (stepS2). When determining that the protrusion 46 is to be cut in step S2(Yes in step S2), the manufacturer cuts the protrusion 46 (step S3).When the protrusion 46 is determined not to be cut in step S2 (No instep S2), or when the processing in step S3 is performed, themanufacturing processes end.

A method for manufacturing a sensor module using the connector chip thatcan connect the first protrusion 464 and the second protrusion 466 willnow be described. FIG. 11 is a flowchart showing a different method formanufacturing the sensor module 4. In step S11, an intermediatecomponent for a second photosensor is prepared. The second photosensorintermediate component differs from the first photosensor intermediatecomponent in that its protrusion 46 consists of the first protrusion 464and the second protrusion 466 and does not include the externalconnector 460. The method for preparing the second photosensorintermediate component is substantially the same as the method describedabove for the first photosensor intermediate component.

When the processing in step S11 completes, the manufacturer prepares aconnector chip that can connect the first protrusion 464 and the secondprotrusion 466 (step S12). The connector chip may be made of anyconductive material. The manufacturer then determines whether the firstprotrusion 464 and the second protrusion 466 in the second photosensorintermediate component are to be connected (step S13). When determiningthat the protrusions are to be connected in step S13 (Yes in step S13),the manufacturer connects the first protrusion 464 and the secondprotrusion 466 with the connector chip by, for example, soldering (stepS14). When the protrusions are determined not to be connected in stepS13 (No in step S13), or when the processing in step S14 is performed,the manufacturing processes end.

Resin for Circuit-Encapsulating Portion, Light Emitter, and LightReceiver

As shown in FIGS. 6 to 8, the circuit-encapsulating portion 90encapsulates the circuit block 40. FIGS. 12A and 12B are side views ofthe sensor module shown in FIG. 7. FIG. 12A is a left side view of thesensor module 4 shown in FIG. 7, and FIG. 12B is a right side view ofthe sensor module 4 shown in FIG. 7. In FIGS. 12A and 12B, the dottedlines indicate the emitter element 11, the receiver element 16, and thelight emitting element 42.

Referring now to FIGS. 7, 8, and 12A and 12B, the circuit-encapsulatingportion 90 includes a circuit encapsulating body 91 and the operationindicator 92. The circuit encapsulating body 91 encapsulates the circuitblock 40. More specifically, the circuit encapsulating body 91encapsulates the integrated circuit 41 with resin. The circuitencapsulating body 91 further encapsulates the light emitting element 42with resin. The operation indicator 92 is arranged on the circuitencapsulating body 91. The operation indicator 92 faces the lightemitting element 42. In other words, the operation indicator 92 allowsthe light emitted from the light emitting element 42 to pass through it.

The emitter encapsulating portion 12, the receiver encapsulating portion17, and the circuit-encapsulating portion 48 are formed from the sameresin containing the same concentration of light diffusing agent. Theemitter encapsulating portion 12, the receiver encapsulating portion 17,and the circuit-encapsulating portion 48 are connected to one anotherthrough the leadframe 8. When the positive direction of Z axis is theupward direction in FIG. 12A, the distance H11 from the upper end of theemitter element 11 to the upper end of the emitter base 13 is smallerthan the distance H21 from the upper end of the light emitting element42 to the upper end of the circuit encapsulating body 91. The positivedirection of Z axis also corresponds to the direction in which theemitter element 11 emits light and also corresponds to the direction inwhich the light emitting element 42 emits light. Thus, the thickness H11of the emitter base 13 in the direction in which the emitter element 11emits light is smaller than the thickness H21 of the circuitencapsulating body 91 in the direction in which the light emittingelement 42 emits light. Additionally, when the positive direction of Zaxis is the upward direction, the distance H12 from the upper end of theemitter base 13 to the upper end (the rear nodal point) V1 of theemitter lens 14 is smaller than the thickness H22 of the operationindicator 92 in the Z-direction. The thickness H12 of the emitter lens19 in the direction in which the emitter element 11 emits light issmaller than the thickness H22 of the operation indicator 92 in thedirection in which the light emitting element 42 emits light. Thus, whenthe positive direction of Z axis is the upward direction, the distanceH1 from the upper end of the emitter element 11 to the upper end V1 ofthe emitter lens 19 is smaller than the distance H2 from the upper endof the light emitting element 42 to the upper end of the operationindicator 92. In other words, the thickness H1 of the emitterencapsulating portion 12 in the direction in which the emitter element11 emits light is smaller than the thickness H2 of thecircuit-encapsulating portion 90 including the thickness of theoperation indicator 92 in the direction in which the light emittingelement 42 emits light. The distance H2 is 1.5 times larger than thedistance H1.

Referring to FIG. 12B, when the positive direction of Z axis is theupward direction, the distance H31 from the upper end of the receiverelement 16 to the upper end of the receiver base 18 is smaller than thedistance H21 from the upper end of the light emitting element 42 to theupper end of the circuit encapsulating body 91. The negative directionof Z axis also corresponds to the direction in which the receiverelement 16 receives light, and the positive direction of Z axis alsocorresponds to the direction in which the light emitting element 42emits light. Thus, the thickness H31 of the receiver base 18 in thedirection in which the receiver element 16 receives light is smallerthan the thickness H21 of the circuit encapsulating body 91 in thedirection in which the light emitting element 42 emits light.Additionally, when the positive direction of Z axis is the upwarddirection, the distance H32 from the upper end of the receiver base 18to the upper end (the rear nodal point) V2 of the receiver lens 19 issmaller than the thickness H22 of the operation indicator 92 in theZ-direction. The thickness H32 of the receiver lens 19 in the directionin which the receiver element 16 receives light is smaller than thethickness H22 of the operation indicator 92 in the direction in whichthe light emitting element 42 emits light. Thus, when the positivedirection of Z axis is the upward direction, the distance H3 from theupper end of the receiver element 16 to the upper end (the rear nodalpoint) V2 of the receiver lens 19 is smaller than the distance H2 fromthe upper end of the light emitting element 42 to the upper end of theoperation indicator 92. In other words, the thickness H3 of the receiverencapsulating portion 17 in the direction in which the receiver element16 receives light is smaller than the thickness H2 of thecircuit-encapsulating portion 90 including the thickness of theoperation indicator 92 in the direction in which the light emittingelement 42 emits light. The distance H2 is 1.5 times larger than thedistance H3.

To increase the sensitivity of the photosensor 1, the light emitted fromthe emitter element 11 and received by the receiver element 16preferably has minimum diffusion, whereas the light emitted from thelight emitting element 42 preferably has maximum diffusion to increasethe visibility of an operator. The thickness H1 of the emitterencapsulating portion 12 is smaller than the thickness H2 of thecircuit-encapsulating portion 90. The thickness H3 of the receiverencapsulating portion 17 is smaller than the thickness H2 of thecircuit-encapsulating portion 90. This setting allows the emitterencapsulating portion 12 and the receiver encapsulating portion 17 toreceive a lower degree of light diffusion and the circuit-encapsulatingportion 90 to receive a higher degree of light diffusion, although theemitter encapsulating portion 12, the receiver encapsulating portion 17,and the circuit-encapsulating portion 48 are formed from the same resincontaining the same concentration of light diffusing agent.

To diffuse light in the circuit-encapsulating portion 90 by a degree toachieve visibility, the resin may contain the light diffusing agent at aconcentration of not less than 0.3% by weight. To obtain a photocurrentfrom the receiver element 16 without affecting the sensitivity of thephotosensor 1, the resin may contain the light diffusing agent at aconcentration of not more than 0.7% by weight. Thus, the resin maypreferably contain the light diffusing agent at a concentration rangingfrom 0.3 to 0.7% by weight. The resin may ideally contain the lightdiffusing agent at a concentration of 0.5% by weight.

Connecting Terminal

Referring to FIG. 8, the connecting terminals 50 include the powersupply connecting terminal 51, a ground (GND) terminal 54, a firstterminal 52, and a third terminal 53. The first terminal 52 and thethird terminal 53 are collectively referred to as a first externalconnecting terminal. The first terminal 52 and the third terminal 53protrude from the circuit-encapsulating portion 90. In other words, thefirst external connecting terminal protrudes from thecircuit-encapsulating portion 90. The power supply connecting terminal51 and the ground terminal 54 are collectively referred to as a secondexternal connecting terminal. The power supply connecting terminal 51and the ground terminal 54 protrude from the circuit-encapsulatingportion 90. In other words, the second external connecting terminalprotrudes from the circuit-encapsulating portion 90.

FIG. 13 is an enlarged view of the connecting terminals 50 and theirsurrounding area. Referring to FIG. 13, the first terminal 52 includes afirst circuit connector 52 a, a first inner terminal 52 c, and a firstouter terminal 52 d. The first circuit connector 52 a is connected tothe integrated circuit 41 with a wire W5. The first circuit connector 52a is a portion to which the wire W5 is connected. The first circuitconnector 52 a is, for example, a rectangular lead shown in FIG. 13. Thefirst circuit connector 52 a may not be rectangular as in FIG. 13.

The first inner terminal 52 c extends from the first circuit connector52 a. More specifically, the first inner terminal 52 c extends to theleft (in the negative direction of X axis) and downward (in the negativedirection of Y axis) from the first circuit connector 52 a. As shown inFIG. 13, the upper end of the first inner terminal 52 c meets the firstcircuit connector 52 a. The lower end of the first inner terminal 52 cis defined by a straight line including a lower distal end PE1 of afirst through-hole 523 and perpendicular to the direction in which thefirst outer terminal 52 d extends (the negative direction of Y axis).The first inner terminal 52 c may extend in a direction different fromthe direction shown in FIG. 13. The first inner terminal 52 c may haveany shape when the width of its portion in contact with thecircuit-encapsulating portion 90 (the length in the directionperpendicular to the direction in which the first inner terminal 52 cextends or to the negative direction of Y axis) is smaller than thewidth of its lower end (the length in the direction perpendicular to thedirection in which the first inner terminal 52 c extends or to thenegative direction of Y axis). The shape of the first inner terminal 52c will be described in detail below.

The first outer terminal 52 d extends from the first inner terminal 52c. More specifically, the first outer terminal 52 d extends downward (inthe negative direction of Y axis) from the first inner terminal 52 c.The first outer terminal 52 d includes a first end 52 b opposite to itsend connected to the first inner terminal 52 c. The first end 52 bincludes a second through-hole 525, which is used for soldering. Thedimension D11 of the first outer terminal 52 d in the directionperpendicular to the direction in which the first outer terminal 52 dextends (X-axis direction) is uniform except for its curved portionaround the first end 52 b.

FIG. 14 is an enlarged view of the first inner terminal 52 c. Referringto FIG. 14, the first inner terminal 52 c includes a first portion 521,a second portion 522, and a third portion 524. The first portion 521includes a first left portion 1521 and a first right portion 2521. Thesecond portion 522 includes a second left portion 1522 and a secondright portion 2522. The first portion 521, the second portion 522, andthe third portion 524 define a first through-hole 523. In other words,the first inner terminal 52 c includes the first through-hole 523.

The first portion 521, which is included in the first inner terminal 52c, is located outside the circuit-encapsulating portion 90. Morespecifically, the upper end of the first portion 521 is located wherethe first inner terminal 52 c and the outline of thecircuit-encapsulating portion 90 overlap as viewed in a directionperpendicular to the first plane (XY plane). The first left portion 1521and the first right portion 2521 are located outside thecircuit-encapsulating portion 90. The first left portion 1521, which isincluded in the first portion 521, is located to the left of the firstthrough-hole 523. The first right portion 2521, which is included in thefirst portion 521, is located to the right of the first through-hole523. The first portion 521 is adjacent to the first outer terminal 52 d.In other words, the first left portion 1521 and the first right portion2521 are adjacent to the first outer terminal 52 d.

The second portion 522 is adjacent to the first portion 521 and islocated inside the circuit-encapsulating portion 90. More specifically,the lower end of the second portion 522 is located where the first innerterminal 52 c and the outline of the circuit-encapsulating portion 90overlap as viewed in a direction perpendicular to the first plane (XYplane). The upper end of the second portion 522 is defined by a straightline including an upper distal end PE3 of a first through-hole 523 asviewed in a direction perpendicular to the direction in which the firstinner terminal 52 c extends (the negative direction of Y axis). Thesecond left portion 1522, which is included in the second portion 522,is located to the left of the first through-hole 523. The second rightportion 2522, which is included in the second portion 522, is located tothe right of the first through-hole 523. In other words, the second leftportion 1522 is adjacent to the first left portion 1521 and is locatedinside the circuit-encapsulating portion 90. The second right portion2522 is adjacent to the first right portion 2521 and is located insidethe circuit-encapsulating portion 90.

The third portion 524 is located nearer the first circuit connector 52 athan the second portion 522. In other words, the third portion 524 islocated nearer the first circuit connector 52 a than the second leftportion 1522 and the second right portion 2522. More specifically, theupper end of the third portion 524 meets the first circuit connector 52a. The lower end of the third portion 524 is defined by a straight lineincluding an upper distal end PE3 of the first through-hole 523 andperpendicular to the direction in which the first inner terminal 52 cextends (the negative direction of Y axis).

The dimension D12 of the first left portion 1521 in the directionperpendicular to the direction in which the first outer terminal 52 cextends (X-axis direction) is smaller than the dimension D11 of thefirst outer terminal 52 d in the direction perpendicular to thedirection in which the first outer terminal 52 d extends (X-axisdirection). Likewise, the dimension D13 of the first right portion 2521in the direction perpendicular to the first inner terminal 52 c extends(X-axis direction) is smaller than the dimension D11 of the first outerterminal 52 d in the direction perpendicular to the direction in whichthe first outer terminal 52 d extends (X-axis direction). The dimensionof the first portion 521 in the direction perpendicular to the directionin which the first inner terminal 52 c extends (X-axis direction) isD12+D13. The dimension D12+D13 of the first portion 521 in the directionperpendicular to the direction in which the first inner terminal 52 cextends (X-axis direction) is smaller than the dimension D11 of thefirst outer terminal 52 d in the direction perpendicular to thedirection in which the first outer terminal 52 d extends (X-axisdirection). The first outer terminal 52 d is soldered when theconnecting terminals 50 are connected to an external circuit. When thefirst outer terminal 52 d is soldered, the heat is transmitted towardthe first circuit connector 52 a. With the dimension D12+D13 of thefirst portion 521 being smaller than the dimension D11 of the firstouter terminal 52 d, less heat is transmitted toward the first circuitconnector 52 a. This structure prevents the wire W5 from beingdisconnected by heat.

The dimension D14 of the second left portion 1522 in the directionperpendicular to the direction in which the first inner terminal 52 cextends (X-axis direction) is smaller than the dimension D12 of thefirst left portion 1521 in the direction perpendicular to the directionin which the first inner terminal 52 c extends (X-axis direction).Likewise, the dimension D15 of the second right portion 2522 in thedirection perpendicular to the direction in which the first innerterminal 52 c extends (X-axis direction) is smaller than the dimensionD13 of the first right portion 2521 in the direction perpendicular tothe direction in which the first inner terminal 52 c extends (X-axisdirection). The dimension D16 of the third portion 524 on its endmeeting the second portion 522 in the direction perpendicular to thedirection in which the first inner terminal 52 c extends (X-axisdirection) is larger than the dimension D14 of the second left portion1522 in the direction perpendicular to the direction in which the firstinner terminal 52 c extends (X-axis direction). Likewise, the dimensionD16 of the third portion 524 on its end meeting the second portion 522in the direction perpendicular to the direction in which the first innerterminal 52 c extends (X-axis direction) is larger than the dimensionD15 of the second right portion 2522 in the direction perpendicular tothe direction in which the first inner terminal 52 c extends (X-axisdirection). The dimension of the second portion 522 in the directionperpendicular to the direction in which the first inner terminal 52 cextends (X-axis direction) is D14+D15. The dimension D16 of the thirdportion 524 on its end meeting the second portion 522 in the directionperpendicular to the direction in which the first inner terminal 52 cextends (X-axis direction) is larger than the dimension D14+D15 of thesecond portion 522 in the direction perpendicular to the direction inwhich the first inner terminal 52 c extends (X-axis direction). When thefirst outer terminal 52 d is soldered, the heat transmitted to thesecond portion 522 can melt the resin portion touching the secondportion 522. However, with the dimension D16 of the third portion 524 onits end meeting the second portion 522 being larger than the dimensionD14+D15 of the second portion 522, the first terminal 52 is less likelyto detach from the circuit-encapsulating portion 90 if the resin portiontouching the second portion 522 melts.

A portion of the first through-hole 523 is filled with the resin. Theportion of the first through-hole 523 filled with the resin is referredto as a first hole encapsulator 93 (refer to FIG. 8). The first holeencapsulator 93 partially encapsulates the first through-hole 523. Inother words, the first through-hole 523 has a portion not filled withresin. The circuit-encapsulating portion 90 is injection molded with theresin injected from an injection port (gate) G shown in FIG. 8. When themolding of the circuit-encapsulating portion 90 is complete, the gate Gis removed, leaving a gate mark on the surface of thecircuit-encapsulating portion 90 as an injection port correspondingportion 97. The injection port corresponding portion 97 is thus at aposition corresponding to the resin injection port G, through whichresin is injected for injection-molding the circuit-encapsulatingportion 90 with resin. As shown in FIG. 8, the first hole encapsulator93 is located on one end of the circuit-encapsulating portion 90,whereas the injection port corresponding portion 97 is located on theother end of the circuit-encapsulating portion 90. This structure cangenerate more voids (bubbles) in the first through-hole 523. If thedimension of the first portion 521 (D12+D13) is large, the firstexternal connecting terminal will trap air, which forms bubbles. Thefirst portion 521 with the dimension (D12+D13) smaller than thedimension D11 of the first outer terminal 52 d reduces the likelihoodthat air will be trapped by the first external connecting terminal.Additionally, reducing the terminal width (D12+D13) reduces the area fortrapping bubbles, and further reduces such bubbles causing insufficientresin filling. The first portion 521 may preferably be long enough inthe direction in which the first inner terminal 52 c extends to preventburrs from forming in the process of injection-molding thecircuit-encapsulating portion 90 with resin.

Referring to FIG. 13, the third terminal 53 includes a third circuitconnector 53 a, a third inner terminal 53 c, and a third outer terminal53 d. The third circuit connector 53 a is connected to the integratedcircuit 41 with a wire W6, a third lead 36, which is a part of the mainlead 30, and wires W7 and W8. The third circuit connector 53 a is aportion to which the wire W6 is connected. The third circuit connector53 a is, for example, a rectangular lead shown in FIG. 13. The thirdcircuit connector 53 a may not be rectangular as in FIG. 13.

The third inner terminal 53 c extends from the third circuit connector53 a. More specifically, the third inner terminal 53 c extends downward(in the negative direction of Y axis) in a staggered manner on a planefrom the third circuit connector 53 a. As shown in FIG. 13, the upperend of the third inner terminal 53 c meets the third circuit connector53 a. The lower end of the third inner terminal 53 c is defined by astraight line including a lower distal end PE2 of a third through-hole533 perpendicular to the direction in which the third outer terminal 53d extends (in the negative direction of Y axis). The third innerterminal 53 c may extend in a direction different from the directionshown in FIG. 13. The third inner terminal 53 c may have any shape whenthe width of its portion in contact with the circuit-encapsulatingportion 90 (the length in the direction perpendicular to the directionin which the third inner terminal 53 c extends or to the negativedirection of Y axis) is smaller than the width of its lower end (thelength in the direction perpendicular to the direction in which thethird inner terminal 53 c extends or to the negative direction of Yaxis). The shape of the third inner terminal 53 c will be described indetail below.

The third outer terminal 53 d extends from the third inner terminal 53c. More specifically, the third outer terminal 53 d extends downward (inthe negative direction of Y axis) from the third inner terminal 53 c.The third outer terminal 53 d includes a third end 53 b opposite to itsend connected to the third inner terminal 53 c. The third end 53 bincludes a fourth through-hole 535, which is used for soldering. Thedimension D21 of the third outer terminal 53 d in the directionperpendicular to the direction in which the third outer terminal 53 dextends (X-axis direction) is uniform except for its curved portionaround the third end 53 b.

FIG. 14 is an enlarged view of the third inner terminal 53 c. Referringto FIG. 14, the third inner terminal 53 c includes a fourth portion 531,a fifth portion 532, and a sixth portion 534. The fourth portion 531includes a fourth left portion 1531 and a fourth right portion 2531. Thefifth portion 532 includes a fifth left portion 1532 and a fifth rightportion 2532. The fourth portion 531, the fifth portion 532, and thesixth portion 534 define a third through-hole 533. In other words, thethird inner terminal 53 c includes the third through-hole 533.

The fourth portion 531, which is included in the third inner terminal 53c, is located outside the circuit-encapsulating portion 90. Morespecifically, the upper end of the fourth portion 531 is located wherethe third inner terminal 53 c and the outline of thecircuit-encapsulating portion 90 overlap as viewed in the directionperpendicular to the first plane (XY plane). The fourth left portion1531 and the fourth right portion 2531 are located outside thecircuit-encapsulating portion 90. The fourth left portion 1531, which isincluded in the fourth portion 531, is located to the left of the thirdthrough-hole 533. The fourth right portion 2531, which is included inthe fourth portion 531, is located to the right of the thirdthrough-hole 533. The fourth portion 531 is adjacent to the third outerterminal 53 d. In other words, the fourth left portion 1531 and thefourth right portion 2531 are adjacent to the third outer terminal 53 d.

The fifth portion 532 is adjacent to the fourth portion 531 and islocated inside the circuit-encapsulating portion 90. More specifically,the lower end of the fifth portion 532 is located where the third innerterminal 53 c and the outline of the circuit-encapsulating portion 90overlap as viewed in the direction perpendicular to the first plane (XYplane). The upper end of the fifth portion 532 is defined by a straightline including an upper distal end PE4 of a third through-hole 533 asviewed in a direction perpendicular to the direction in which the thirdinner terminal 53 c extends (the negative direction of Y axis). Thefifth left portion 1532, which is included in the fifth portion 532, islocated to the left of the third through-hole 533. The fifth rightportion 2532, which is included in the fifth portion 532, is located tothe right of the third through-hole 533. In other words, the fifth leftportion 1532 is adjacent to the fourth left portion 1531 and is locatedinside the circuit-encapsulating portion 90. The fifth right portion2532 is adjacent to the fourth right portion 2531 and is located insidethe circuit-encapsulating portion 90.

The sixth portion 534 is located nearer the third circuit connector 53 athan the fifth portion 532. In other words, the sixth portion 534 islocated nearer the third circuit connector 53 a than the fifth leftportion 1532 and the fifth right portion 2532. More specifically, theupper end of the sixth portion 534 meets the third circuit connector 53a. The lower end of the sixth portion 534 is defined by a straight lineincluding the upper distal end PE4 of the third through-hole 533 andperpendicular to the direction in which the third inner terminal 53 cextends (to the negative direction of Y axis).

The dimension D22 of the fourth left portion 1531 in the directionperpendicular to the direction in which the third outer terminal 53 cextends (X-axis direction) is smaller than the dimension D21 of thethird outer terminal 53 d in the direction perpendicular to thedirection in which the third outer terminal 53 d extends (X-axisdirection). Likewise, the dimension D23 of the fourth right portion 2531in the direction perpendicular to the direction in which the third outerterminal 53 c extends (X-axis direction) is smaller than the dimensionD21 of the third outer terminal 53 d in the direction perpendicular tothe direction in which the third outer terminal 53 d extends (X-axisdirection). The dimension of the fourth portion 531 in the directionperpendicular to the direction in which the third inner terminal 53 cextends (X-axis direction) is D22+D23. The dimension D22+D23 of thefourth portion 531 in the direction perpendicular to the direction inwhich the third inner terminal 53 c extends

(X-axis direction) is smaller than the dimension D21 of the third outerterminal 53 d in the direction perpendicular to the direction in whichthe third outer terminal 53 d extends (X-axis direction). The thirdouter terminal 53 d is soldered when the connecting terminals 50 areconnected to an external circuit. When the third outer terminal 53 d issoldered, the heat is transmitted toward the third circuit connector 53a. With the dimension D22+D23 of the fourth portion 531 being smallerthan the dimension D21 of the third outer terminal 53 d, less heat istransmitted toward the third circuit connector 53 a. This structureprevents the wires W6 and W7 from being disconnected by heat.

The dimension D24 of the fifth left portion 1532 in the directionperpendicular to the direction in which the third inner terminal 53 cextends (X-axis direction) is smaller than the dimension D22 of thefourth left portion 1531 in the direction perpendicular to the directionin which the third inner terminal 53 c extends (X-axis direction).Likewise, the dimension D25 of the fifth right portion 2532 in thedirection perpendicular to the direction in which the third innerterminal 53 c extends (X-axis direction) is smaller than the dimensionD23 of the fourth right portion 2531 in the direction perpendicular tothe direction in which the third inner terminal 53 c extends (X-axisdirection). The dimension D26 of the sixth portion 534 in the directionperpendicular to the direction in which the third inner terminal 53 cextends (X-axis direction) is larger than the dimension D24 of the fifthleft portion 1532 in the direction perpendicular to the direction inwhich the third inner terminal 53 c extends (X-axis direction). Thedimension D26 of the sixth portion 534 in the direction perpendicular tothe direction in which the third inner terminal 53 c extends (X-axisdirection) is larger than the dimension D25 of the fifth right portion2532 in the direction perpendicular to the direction in which the thirdinner terminal 53 c extends (X-axis direction). The dimension of thefifth portion 532 in the direction perpendicular to the direction inwhich the third inner terminal 53 c extends (X-axis direction) isD24+D25. The dimension D26 of the sixth portion 534 in the directionperpendicular to the direction in which the third inner terminal 53 cextends (X-axis direction) is larger than the dimension D24+D25 of thefifth portion 532 in the direction perpendicular to the direction inwhich the third inner terminal 53 c extends (X-axis direction). When thethird outer terminal 53 d is soldered, the heat transmitted to the fifthportion 532 can melt the resin portion touching the fifth portion 532.However, with the dimension D26 of the sixth portion 534 being largerthan the dimension D24+D25 of the fifth portion 532, the third terminal53 is less likely to be detached from the circuit-encapsulating portion90 if the resin portion touching the fifth portion 532 melts.

A portion of the third through-hole 533 is filled with the resin. Theportion of the third through-hole 533 filled with the resin is referredto as a third hole encapsulator 94 (refer to FIG. 8). The third holeencapsulator 94 partially encapsulates the third through-hole 533. Inother words, the third through-hole 533 has a portion not filled withresin. The third hole encapsulator 94 is located on one end of thecircuit-encapsulating portion 90, whereas the injection portcorresponding portion 97 is located on the other end of thecircuit-encapsulating portion 90. This structure can generate more voids(bubbles) in the third through-hole 533. If the dimension of the fourthportion 531 (D22+D23) is large, the first external connecting terminalwill trap air, which forms bubbles. The fourth portion 531 with thedimension (D22+D23) smaller than the dimension D21 of the third outerterminal 53 d reduces the likelihood that air will be trapped by thefirst external connecting terminal. Additionally, reducing the terminalwidth (D22+D23) reduces the area for to trapping bubbles, and furtherreduces such bubbles causing insufficient resin filling. The fourthportion 531 may preferably be long enough in its direction in which thethird inner terminal 53 c extends to prevent burrs from forming in theprocess of injection-molding the circuit-encapsulating portion 90 withresin.

Referring to FIG. 13, the power supply terminal 51 includes a secondcircuit connector 51 a, a second inner terminal 51 c, and a second outerterminal 51 d. The second circuit connector 51 a is connected to theintegrated circuit 41 with the wires W2 and W3, the second lead 34, andthe wire W4. The second inner terminal 51 c extends from the secondcircuit connector 51 a. More specifically, the second inner terminal 51c extends to the left (in the negative direction of X axis) from thesecond circuit connector 51 a. The second outer terminal 51 d extendsfrom the second inner terminal 51 c. More specifically, the second outerterminal 51 d extends downward (in the negative direction of Y axis)from the second inner terminal 51 c. The second outer terminal 51 dincludes a second end 54 b opposite to its end connected to the fourthterminal 54 c. The second end 51 b includes a fifth through-hole 515,which is used for soldering. The dimension of the second outer terminal51 d in the direction perpendicular to the direction in which the secondouter terminal 51 d extends (X-axis direction) is substantially uniform.

The ground terminal 54 includes a fourth circuit connector 54 a, afourth inner terminal 54 c, and a fourth outer terminal 54 d. The fourthcircuit connector 54 a is connected to the integrated circuit 41 withthe first receiver lead 24 and a wire W9. The fourth inner terminal 54 cextends from the fourth circuit connector 54 a. More specifically, thefourth inner terminal 54 c extends downward (in the negative directionof Y axis) and to the right (the positive direction of X axis) from thefourth circuit connector 54 a. The fourth outer terminal 54 d extendsfrom the fourth inner terminal 54 c. More specifically, the fourth outerterminal 54 d extends downward (in the negative direction of Y axis)from the fourth inner terminal 54 c. The fourth outer terminal 54 dincludes a fourth end 54 b opposite to its end connected to the fourthterminal 54 c. The fourth end 54 b includes a sixth through-hole 545,which is used for soldering. The dimension of the fourth outer terminal54 d in the direction perpendicular to the direction in which the fourthouter terminal 54 d extends (X-axis direction) is substantially uniform.

The distance between the second through-hole 525 and the first circuitconnector 52 a is smaller than the distance between the fifththrough-hole 515 and the second circuit connector 51 a. Likewise, thedistance between the fourth through-hole 535 and the third circuitconnector 53 a is smaller than the distance between the fifththrough-hole 515 and the second circuit connector 51 a. Further, thedistance between the second through-hole 525 and the first circuitconnector 52 a is smaller than the distance between the sixththrough-hole 545 and the fourth circuit connector 54 a. Likewise, thedistance between the fourth through-hole 535 and the third circuitconnector 53 a is smaller than the distance between the sixththrough-hole 545 and the fourth circuit connector 54 a. The distancebetween the two parts does not refer to a distance on a straight linejoining the two parts, but refers to the smallest distance on the leadjoining the two parts. Each of the power supply terminal 51 and theground terminal 54 has a long distance from its end to the circuitconnector, and thus easily cools when heat is transmitted from the endto the circuit connector. In contrast, each of the first terminal 52 andthe third terminal 53 has a small distance from its end to the circuitconnector, and thus does not easily cool when heat is transmitted fromthe end to the circuit connector. To reduce heat transmission, the firstterminal 52 has the first through-hole 523, and the third terminal 53has the third through-hole 533.

The surface area of the first terminal 52 is smaller than the surfacearea of each of the power supply terminal 51 and the ground terminal 54.The surface area of the third terminal 53 is smaller than the surfacearea of each of the power supply terminal 51 and the ground terminal 54.Each of the power supply terminal 51 and the ground terminal 54 has alarge surface area, and thus can cool easily when heat is transmittedfrom its end toward the circuit connector. In contrast, each of thefirst terminal 52 and the third terminal 53 has a small surface area,and thus does not cool easily when heat is transmitted from its end tothe circuit connector. To reduce heat transmission, the first terminal52 has the first through-hole 523, and the third terminal 53 has thethird through-hole 533.

As described above, the first outer terminal 52 d and the third outerterminal 53 d extend in the same direction and have the same shape. Thewidths of the first inner terminal 52 c and the third inner terminal 53c on their sides in contact with the circuit-encapsulating portion 90are narrower than the widths of the first inner terminal 52 c and thethird inner terminal 53 c on their lower ends. Thus, the first circuitconnector 52 a and the third circuit connector 53 a may be replaced witheach other. The first inner terminal 52 c and the third inner terminal53 c may be replaced with each other. The first outer terminal 52 d andthe third outer terminal 53 d may be replaced with each other. The firstend 52 b and the third end 53 b may be replaced with each other. Thefirst portion 521 and the fourth portion 531 may be replaced with eachother. The second portion 522 and the fifth portion 532 may be replacedwith each other. The third portion 524 and the sixth portion 534 may bereplaced with each other. The first through-hole 523 and the thirdthrough-hole 533 may be replaced with each other. The first holeencapsulator 93 and the third hole encapsulator 94 may be replaced witheach other.

Likewise, the second outer terminal 51 d and the fourth outer terminal54 d extend in the same direction. Thus, the second circuit connector 51a and the fourth circuit connector 54 a may be replaced with each other.The second inner terminal 51 c and the fourth inner terminal 54 c may bereplaced with each other. The second outer terminal 51 d and the fourthouter terminal 54 d may be replaced with each other.

The first inner terminal 52 c and the third inner terminal 53 c may nothave the through-holes 523 and 533. FIG. 15A and FIG. 15B show firstinner terminals and third inner terminals according to modifications ofthe present embodiment. As shown in FIG. 15A(a), for example, a firstterminal 152 includes a first inner terminal 152 c, a first circuitconnector 52 a, and a first outer terminal 52 d. The first innerterminal 152 c includes a first left portion 1521 and a second leftportion 1522. A third terminal 153 includes a third inner terminal 153c, a third circuit connector 53 a, and a third outer terminal 53 d. Thethird inner terminal 153 c includes a fourth left portion 1531 and afifth left portion 1532. As shown in FIG. 15A(b), a first terminal 252includes a first inner terminal 252 c, a first circuit connector 52 a,and a first outer terminal 52 d. The first terminal 252 includes a firstright portion 2521 and a second right portion 2522. A third terminal 253includes a third inner terminal 253 c, a third circuit connector 53 a,and a third outer terminal 53 d. The third inner terminal 253 c includesa fourth right portion 2531 and a fifth right portion 2532. Thisstructure also reduces the likelihood that air is trapped by the firstexternal connecting terminal, and reduces insufficient resin filling.

In another example FIG. 15B(c), a first terminal 352 includes a firstinner terminal 352 c, a first circuit connector 52 a, and a first outerterminal 52 d. The first inner terminal 352 c includes a first leftportion 1521, a second left portion 1522, and a third portion 524. Athird terminal 353 includes a third inner terminal 353 c, a thirdcircuit connector 53 a, and a third outer terminal 53 d. The third innerterminal 353 c includes a fourth left portion 1531, a fifth left portion1532, and a sixth portion 534. In still another example shown in FIG.15B(d), a first terminal 452 includes a first inner terminal 452 c, afirst circuit connector 52 a, and a first outer terminal 52 d. The firstinner terminal 452 c includes a first right portion 2521, a second rightportion 2522, and a third portion 524. A third terminal 453 includes athird inner terminal 453 c, a third circuit connector 53 a, and a thirdouter terminal 53 d. The third inner terminal 453 c includes a fourthright portion 2531, a fifth right portion 2532, and a sixth portion 534.These structures reduce the likelihood that air is trapped by theexternal connecting terminal and reduce insufficient resin filling, andfurther prevent the first terminals 352 and 452 and the third terminals353 and 453 from easily detaching from the circuit-encapsulating portion90 when the resin on the second portion or the fifth portion melts.

The photosensor of the present invention may include any of the firstterminals 52, 152, 252, 352, and 452 as its first terminal, and any ofthe third terminals 53, 153, 253, 353, and 453 as its third terminal.

Emitter Lead and Receiver Lead

With the limited arrangement of pins of the integrated circuit 41 in thecircuit-encapsulating portion 90, the sensor module 5 includes theemitter leads 20 and 22 and the receiver leads 24 and 26 that protrudeto the left and to the right. The sensor module 5 can be mounted on aflat (straight) type or an outer L-shaped type. The first emitter lead20, the second emitter lead 22, the first receiver lead 24, and thesecond receiver lead 26 have the characteristics described below. Asshown in FIG. 7, the first emitter lead 20 includes a first emitter leadportion 202, a second emitter lead portion 204, a third emitter leadportion 206, a fourth emitter lead portion 208, and a fifth emitter leadportion 210.

As shown in FIG. 6, the first emitter lead portion 202 protrudes in adirection parallel to the first plane (XY plane) described above andintersecting with the first direction described above (the negativedirection of Y axis) from the circuit-encapsulating portion 90 andextends in a direction opposite to the first direction. Morespecifically, the first emitter lead portion 202 includes a firstemitter lead protrusion 202 a, a first bending portion 202 c, and afirst emitter lead extension 202 b. The first emitter lead protrusion202 a protrudes in the direction parallel to the first plane andintersecting with the first direction from the circuit-encapsulatingportion 90. The first bending portion 202 c joins the first emitter leadprotrusion 202 a and the first emitter lead extension 202 b. The firstemitter lead extension 202 b extends from the first bending portion 202c to the first outer end 204 b of the second emitter lead portion 204 ina direction opposite to the first direction (the positive direction of Yaxis). The first emitter lead protrusion 202 a is long enough (about 0.3to 0.4 mm) to allow deburring after the process of injection-molding thecircuit-encapsulating portion 90.

The second emitter lead portion 204 includes a first outer end 204 b, afirst inner end 204 a, and a first straight portion 204 c. The firstouter end 204 b joins the first emitter lead extension 202 b and thefirst straight portion 204 c. The first outer end 204 b is bent. Thefirst straight portion 204 c extends inward in the optical axisdirection (X-axis direction) from the first outer end 204 b to the firstinner end 204 a. Being inward refers to being toward the plane C1described above in the optical axis direction (X-axis direction). Beingoutward refers to being away from the plane C1 in the optical axisdirection (X-axis direction). The first inner end 204 a joins the firststraight portion 204 c and the third emitter lead portion 206. The firstinner end 204 a is bent. The third emitter lead portion 206 is connectedto the second emitter lead portion 204. More specifically, the thirdemitter lead portion 206 extends in the direction opposite to the firstdirection (the positive direction of Y axis) from the first inner end204 a to a second inner end 208 a (described later) of the fourthemitter lead portion 208.

The fourth emitter lead portion 208 includes a second outer end 208 b, asecond inner end 208 a, and a second straight portion 208 c. The secondinner end 208 a joins the third emitter lead portion 206 and the secondstraight portion 208 c. The second inner end 208 a is bent. The secondstraight portion 208 c extends outward in the optical axis direction(X-axis direction) from the second inner end 208 a to the second outerend 208 b. Referring to FIG. 7, the fourth emitter lead portion 208 isbent at its first bending portion B1 to allow the light emitter 10 andthe light receiver 15 to face each other. As shown in FIG. 6, the fourthemitter lead portion 208 is bent at the first bending portion B1 so thatthe first bending portion B1 and the second outer end 208 b overlap witheach other as viewed in the direction perpendicular to the first plane(XY plane). As shown in FIG. 6, the first inner end 204 a is locatedmore inward than the second outer end 208 b as viewed in the opticalaxis direction (X-axis direction). In the optical axis direction, thesecond inner end 208 a is located more inward than the first outer end204 b. This positional relationship results from the third emitter leadportion 206 arranged inward to allow the first bending portion B1 tohave a sufficient margin for bending in the fourth emitter lead portion208.

The second outer end 208 b joins the second straight portion 208 c andthe fifth emitter lead portion 210. The second outer end 208 b is bent.The fifth emitter lead portion 210 is connected to the second outer end208 b. The fifth emitter lead portion 210 bends and extends in thedirection opposite to the first direction (the positive direction of Yaxis) from the second outer end 208 b to the light emitter 10.

Referring to FIGS. 6 and 7, the second emitter lead 22 is located moreinward than the first emitter lead 20 in the optical axis directions(X-axis direction). The second emitter lead 22 includes a sixth emitterlead 222, a third bending portion 223, a seventh emitter lead portion224, a fourth bending portion 225, an eighth emitter lead portion 226, afifth bending portion 227, a ninth emitter lead 228, a sixth bendingportion 229, a tenth emitter lead portion 230, a seventh bending portion231, an eleventh emitter lead 232, an eighth bending portion 233, and atwelfth emitter lead 234.

The sixth emitter lead 222 protrudes in the direction parallel to thefirst plane (XY plane) and intersecting with the first direction (thenegative direction of Y axis) from the circuit-encapsulating portion 90,and extends in the direction opposite to the first direction. Morespecifically, the sixth emitter lead 222 includes a sixth emitter leadprotrusion 222 a, a second bending portion 222 c, and a sixth emitterlead extension 222 b. The sixth emitter lead protrusion 222 a protrudesin the direction parallel to the first plane and intersecting with thefirst direction from the circuit-encapsulating portion 90. The secondbending portion 222 c joins the sixth emitter lead protrusion 222 a andthe sixth emitter lead extension 222 b. The sixth emitter lead extension222 b extends from the second bending portion 222 c to the third bendingportion 223 in the direction opposite to the first direction (thepositive direction of Y axis). The sixth emitter lead protrusion 222 ais long enough (about 0.3 to 0.4 mm) to allow deburring after theprocess of injection-molding the circuit-encapsulating portion 90. Asshown in FIG. 6, the distance D1 between the second emitter lead 22 andthe first emitter lead portion 202 (specifically, the distance D1between the sixth emitter lead extension 222 b and the first emitterlead extension 202 b) is set to prevent contact between and achieveinsulation between the first emitter lead 20 and the second emitter lead22.

The third bending portion 223 joins the sixth emitter lead 222 and theseventh emitter lead portion 224. The seventh emitter lead portion 224extends in the direction opposite to the first direction (the negativedirection of Y axis) and inward from the third bending portion 223 tothe fourth bending portion 225. The seventh emitter lead portion 224corresponds to an inclined light emitting portion, which is inclined toincrease its distance to the first emitter lead portion 202 in theoptical axis direction.

The fourth bending portion 225 joins the seventh emitter lead portion224 and the eighth emitter lead portion 226. The eighth emitter leadportion 226 is connected to the seventh emitter lead portion 224. Morespecifically, the eighth emitter lead portion 226 extends in thedirection opposite to the first direction (the positive direction of Yaxis) from the fourth bending portion 225 to the fifth bending portion227. As shown in FIG. 6, the distance D2 between the second emitter lead22 and the third emitter lead portion 206 (specifically, the distance D2between the eighth emitter lead portion 226 and the third emitter leadportion 206) is set to prevent contact between and achieve insulationbetween the first emitter lead 20 and the second emitter lead 22. Thedistance D2 between the second emitter lead 22 and the third emitterlead portion 206 is smaller than the distance D1 between the secondemitter lead 22 and the first emitter lead portion 202. This resultsfrom the third emitter lead portion 206 arranged most inward to allowthe first bending portion B1 (described below) to have a sufficientmargin for bending in the fourth emitter lead portion 208.

The fifth bending portion 227 joins the eighth emitter lead portion 226and the ninth emitter lead 228. The ninth emitter lead 228 extendsoutward in the optical axis direction (X-axis direction) (in thedirection opposite to the direction in which the seventh emitter leadportion 224 is inclined with respect to the optical axis direction, orthe X-axis direction) from the fifth bending portion 227 to the sixthbending portion 229. The sixth bending portion 229 joins the ninthemitter lead 228 and the tenth emitter lead portion 230. The tenthemitter lead portion 230 is connected to the ninth emitter lead 228.More specifically, the tenth emitter lead portion 230 extends from thesixth bending portion 229 to the seventh bending portion 231 in thedirection opposite to the first direction (the positive direction of Yaxis). The seventh bending portion 231 joins the tenth emitter leadportion 230 and the eleventh emitter lead 232. The eleventh emitter lead232 extends in the direction opposite to the first direction (thenegative direction of Y axis) and inward from the seventh bendingportion 231 to the eighth bending portion 233. The eleventh emitter lead232 is inclined to increase its distance to the first emitter lead 20 inthe optical axis direction. The eighth bending portion 233 joins theeleventh emitter lead 232 and the twelfth emitter lead 234. The twelfthemitter lead 234 is connected to the eighth bending portion 233 andextends in the direction opposite to the first direction (the positivedirection of Y axis) to the light emitter 10.

As shown in FIGS. 6 and 7, the first receiver lead 24 includes a firstreceiver lead portion 242, a second receiver lead portion 244, a thirdreceiver lead portion 246, a fourth receiver lead portion 248, and afifth receiver lead portion 250.

As shown in FIG. 6, the first receiver lead portion 242 protrudes fromthe circuit-encapsulating portion 90 in the direction parallel to thefirst plane (XY plane) and intersecting with the first direction (thenegative direction of Y axis) and in the direction opposite to thedirection in which the first emitter lead 20 and the second emitter lead22 protrude. More specifically, the first receiver lead portion 242includes a first receiver lead protrusion 242 a, a ninth bending portion242 c, and a first receiver extension 242 b. The first receiver leadprotrusion 242 a protrudes in the direction parallel to the first planeand intersecting with the first direction from the circuit-encapsulatingportion 90 to the first bending portion 202 c. The first bending portion202 c joins the first receiver lead protrusion 242 a and the firstreceiver lead protrusion 242 a. The first receiver extension 242 bextends in the direction opposite to the first direction (the positivedirection of Y axis) from the first bending portion 202 c to the outerend 244 b of the second receiver lead portion 244. The sixth emitterlead protrusion 222 a is long enough (about 0.3 to 0.4 mm) to allowdeburring after the process of injection-molding thecircuit-encapsulating portion 90.

The second receiver lead portion 244 includes a third outer end 244 b, athird inner end 244 a, and a third straight portion 244 c. The thirdouter end 244 b joins the first receiver extension 242 b and the thirdstraight portion 244 c. The third outer end 244 b is bent. The thirdstraight portion 244 c extends inward in the optical axis direction(X-axis direction) from the third outer end 244 b to the third inner end244 a. The third inner end 244 a joins the third straight portion 244 cand the third receiver lead portion 246. The third inner end 244 a isbent. The third receiver lead portion 246 is connected to the secondreceiver lead portion 244. More specifically, the third receiver leadportion 246 extends in the direction opposite to the first direction(the positive direction of Y axis) from the third inner end 244 a to afourth inner end 248 a (described below) of the fourth receiver leadportion 248.

The fourth receiver lead portion 248 includes a fourth outer end 248 b,a fourth inner end 248 a, and a fourth straight portion 248 c. Thefourth inner end 248 a joins the third receiver lead portion 246 and thefourth straight portion 248 c. The fourth inner end 248 a is bent. Thefourth straight portion 248 c extends outward in the optical axisdirection (X-axis direction) from the fourth inner end 248 a to thefourth outer end 248 b. Referring to FIG. 7, the fourth receiver leadportion 248 is bent at its second bending portion B2 to allow the lightemitter 10 and the light receiver 15 to face each other. As shown inFIG. 6, the fourth receiver lead portion 248 is bent at the secondbending portion B2 so that the second bending portion B2 and the fourthouter end 248 b overlap with each other as viewed in the directionperpendicular to the first plane (XY plane). As shown in FIG. 6, thefirst inner end 244 a of the second receiver portion 244 is located moreinward than the fourth outer end 248 b in the optical axis direction(X-axis direction). In the optical axis direction, the fourth inner end248 a is located more inward than the third outer end 244 b. Thispositional relationship results from the third receiver lead portion 246arranged inward to allow the second bending portion B2 to have asufficient margin for bending in the fourth receiver lead portion 248.

The fourth outer end 248 b joins the fourth straight portion 248 c andthe fifth receiver lead portion 250. The fourth outer end 248 b is bent.The fifth receiver lead portion 250 is connected to the fourth outer end248 b. The fifth receiver lead portion 250 bends and extends in thedirection opposite to the first direction (the positive direction of Yaxis) from the fourth outer end 248 b to the light receiver 15.

Referring to FIGS. 6 and 7, the second receiver lead 26 is located moreinward than the first receiver lead 24 in the optical axis direction(X-axis direction). The second receiver lead 26 includes a sixthreceiver lead portion 262, an eleventh bending portion 263, a seventhreceiver lead portion 264, a twelfth bending portion 265, an eighthreceiver lead portion 266, a thirteenth bending portion 267, a ninthreceiver lead portion 268, a fourteenth bending portion 269, a tenthreceiver lead portion 270, a fifteenth bending portion 271, an eleventhreceiver lead portion 272, a sixteenth bending portion 273, and atwelfth receiver lead portion 274.

The sixth receiver lead portion 262 protrudes from thecircuit-encapsulating portion 90 in the direction parallel to the firstplane (XY plane) and intersecting with the first direction (the negativedirection of Y axis) and in the direction opposite to the direction inwhich the first emitter lead 20 and the second emitter lead 22 protrude,and in the direction opposite to the first direction. More specifically,the sixth receiver lead portion 262 includes a sixth receiver leadprotrusion 262 a, a tenth bending portion 262 c, and a sixth receiverextension 262 b. The sixth receiver lead protrusion 262 a protrudes fromthe circuit-encapsulating portion 90 in the direction parallel to thefirst plane and intersecting with the first direction and in thedirection opposite to the direction in which the first emitter lead 20and the second emitter lead 22 protrude. The tenth bending portion 262 cjoins the sixth receiver lead protrusion 262 a and the sixth receiverextension 262 b. The sixth receiver extension 262 b extends in thedirection opposite to the first direction from the tenth bending portion262 c to the eleventh bending portion 263. The sixth receiver leadprotrusion 262 a is long enough (about 0.3 to 0.4 mm) to allow deburringafter the process of injection-molding the circuit-encapsulating portion90. As shown in FIG. 6, the distance D3 between the second receiver lead26 and the first receiver lead portion 242 (specifically, the distanceD3 between the sixth receiver extension 262 b and the first receiverextension 242 b) is set to prevent contact between and achieveinsulation between the first emitter lead 20 and the second emitter lead22.

The eleventh bending portion 263 joins the sixth receiver lead portion262 and the seventh receiver lead portion 264. The seventh receiver leadportion 264 extends in the direction opposite to the first direction(the negative direction of Y axis) and inward from the eleventh bendingportion 263 to the twelfth bending portion 265.

The seventh receiver lead portion 264 corresponds to an inclined lightreceiving portion, which is inclined to increase its distance to thesixth receiver lead portion 262 in the optical axis direction.

The twelfth bending portion 265 joins the seventh receiver lead portion264 and the eighth receiver lead portion 266. The eighth receiver leadportion 266 is connected to the seventh receiver lead portion 264. Morespecifically, the eighth receiver lead portion 266 extends in thedirection opposite to the first direction (the positive direction of Yaxis) from the twelfth bending portion 265 to the thirteenth bendingportion 267. As shown in FIG. 6, the distance D4 between the secondreceiver lead 26 and the third receiver lead portion 246 (specifically,the distance D4 between the eighth receiver lead portion 266 and thethird receiver lead portion 246) is set to prevent contact between andachieve insulation between the first receiver lead 20 and the secondreceiver lead 22. The distance D4 between the second receiver lead 26and the third receiver lead portion 246 is smaller than the distance D3between the second receiver lead 26 and the first receiver lead portion242. This results from the third receiver lead portion 246 arranged mostinward to allow the second bending portion B2 (described below) to havea sufficient margin for bending in the fourth receiver lead portion 208.

The thirteenth bending portion 267 joins the eighth receiver leadportion 266 and the ninth receiver lead portion 268. The ninth receiverlead portion 268 extends outward in the optical axis direction (X-axisdirection) (the direction opposite to the direction in which the seventhreceiver lead portion 264 is inclined with respect to the optical axisdirection or the X-axis direction) from the thirteenth bending portion267 to the fourteenth bending portion 269. The fourteenth bendingportion 269 joins the ninth receiver lead portion 268 and the tenthreceiver lead portion 270. The tenth receiver lead portion 270 isconnected to the ninth receiver lead portion 268. More specifically, thetenth receiver lead portion 270 extends in the direction opposite to thefirst direction (the positive direction of Y axis) from the fourteenthbending portion 269 to the fifteenth bending portion 271. The fifteenthbending portion 271 joins the tenth receiver lead portion 270 and theeleventh receiver lead portion 272. The eleventh receiver lead portion272 extends in the direction opposite to the first direction (thenegative direction of Y axis) and inward from the fifteenth bendingportion 271 to the sixteenth bending portion 273. The eleventh receiverlead portion 272 is inclined to increase its distance to the firstreceiver lead 24 in the optical axis direction. The sixteenth bendingportion 273 joins the eleventh receiver lead portion 272 and the twelfthreceiver lead portion 274. The twelfth receiver lead portion 274 isconnected to the eighth bending portion 233, and extends in thedirection opposite to the first direction (the positive direction of Yaxis) to the light emitter 10.

To shape the primary molded piece (sensor module 4) of the sensor module5 shown in FIG. 7 into the structure shown in FIG. 6 in which the lightemitter 10 and the light receiver 15 face each other, the first emitterlead 20 and the second emitter lead 22 are bent along a first bendingline L1. The first receiver lead 24 and the second receiver lead 26 arebent along a second bending line L2. The first bending line L1 isparallel to a second direction (Y-axis direction) that is perpendicularto the optical axis. The second bending line L2 is also parallel to thesecond direction (Y-axis direction). More specifically, the fourthemitter lead portion 208 includes the first bending portion B1, which isbent along the first bending line L1. The fourth receiver lead portion248 includes the second bending portion B2, which is bent along thesecond bending line L2. The ninth emitter lead 228 includes the thirdbending portion B3, which is bent along the first bending line L1. Theninth receiver lead portion 268 includes a fourth bending portion B4,which is bent along the second bending line L2.

As shown in FIG. 7, when the first emitter lead 20 and the secondemitter lead 22 are unfolded in a plane without bending along the firstbending line L1, the unfolded first emitter lead 20 and the unfoldedsecond emitter lead 22 extend across the first bending line L1. When thefirst receiver lead 24 and the second receiver lead 26 are unfolded in aplane without bending along the second bending line L2, the unfoldedfirst receiver lead 24 and the unfolded second receiver lead 26 extendacross the second bending line L2.

The first emitter lead 20, the second emitter lead 22, the firstreceiver lead 24, and the second receiver lead 26 are wide enough (e.g.,not less than 0.5 mm) to have strength to bend and also to support thelight emitter 10 and the light receiver 15. To have such strength, thefirst emitter lead 20, the second emitter lead 22, the first receiverlead 24, and the second receiver lead 26 are preferably formed from acopper alloy, gold, silver, or a nickel alloy. The distance between thefifth emitter lead portion 210 and the eighth emitter lead portion 226in the optical axis direction is smaller than the total of a verticalwidth D31 and a horizontal width D32 of the emitter case section 62(refer to FIG. 2). The distance between the fifth receiver lead portion250 and the eighth receiver lead portion 266 in the optical axisdirection is smaller than the total of a vertical width D31 and ahorizontal width D33 of the receiver case section 63 (refer to FIG. 2).This structure allows the emitter case section 62 and the receiver casesection 63, which satisfy the industry standards, to accommodate theemitter leads 20 and 22 and the receiver leads 24 and 26.

The shapes of the first emitter lead 20, the second emitter lead 22, thefirst receiver lead 24, and the second receiver lead 26 shown in FIGS. 6to 8 are mere examples. The first emitter lead 20, the second emitterlead 22, the first receiver lead 24, and the second receiver lead 26 maybe in any shapes that can satisfy the four conditions described below.

-   Condition 1: For the unfolded first emitter lead 20 as shown in FIG.    7, the maximum distance between the first emitter lead 20 and the    bending line L1 in the X-axis direction (the distance between the    fifth emitter lead portion 210 and the bending line L1 in the X-axis    direction) is smaller than the vertical width D31 of the emitter    case section 62 shown in FIG. 2.-   Condition 2: For the unfolded second emitter lead 22 as shown in    FIG. 7, the maximum distance between the second emitter lead 22 and    the bending line L1 in the X-axis direction (the distance between    the eighth emitter lead portion 226 and the bending line L1 in the    X-axis direction) is smaller than the horizontal width D32 of the    emitter case section 62 shown in FIG. 2.-   Condition 3: For the unfolded first receiver lead 24 as shown in    FIG. 7, the maximum distance between the first receiver lead 24 and    the bending line L2 in the X-axis direction (the distance between    the fifth receiver lead portion 250 and the bending line L2 in the    X-axis direction) is smaller than the vertical width D31 of the    receiver case section 63 shown in FIG. 2.-   Condition 4: For the unfolded second receiver lead 26 as shown in    FIG. 7, the maximum distance between the second receiver lead 26 and    the bending line L2 in the X-axis direction (the distance between    the eighth receiver lead portion 266 and the bending line L2 in the    X-axis direction) is smaller than the horizontal width D33 of the    receiver case section 63 shown in FIG. 2.

FIG. 16 is a plan view of a sensor module 5 a according to amodification. FIG. 17 is a plan view of a primary molded piece of thesensor module 5 a shown in FIG. 16. In other words, FIG. 17 is anunfolded view of the sensor module 5 a according to the modification inFIG. 16. The sensor module 5 a unfolded in a plane shown in FIG. 17 ishereafter referred to as a sensor module 4 a. In FIGS. 16 and 17, thecomponents that are the same as the components shown in FIGS. 6 and 7are given the same reference numerals as those components and will notbe described.

Referring to FIGS. 16 and 17, the sensor module 5 a includes a firstemitter lead 21, a second emitter lead 23, a first receiver lead 25, anda second receiver lead 27. The first emitter lead 21, the second emitterlead 23, the first receiver lead 25, and the second receiver lead 27 areflat plates. The first emitter lead 21 and the second emitter lead 23connect the light emitter 10 and the circuit-encapsulating portion 90.The first emitter lead 21 and the second emitter lead 23 are parallel tothe first plane (XY) described above and protrude in the directionintersecting with the first direction (to the left, or in the negativedirection of X axis) from the circuit-encapsulating portion 90. Thefirst emitter lead 21 and the second emitter lead 23 extend in thedirection opposite to the first direction (the positive direction of Yaxis). The first receiver lead 25 and the second receiver lead 27connect the light receiver 15 and the circuit-encapsulating portion 90.The first receiver lead 25 and the second receiver lead 27 are parallelto the first plane and protrude in the direction intersecting with thefirst direction and in the direction opposite to the direction in whichthe first emitter lead 21 and the second emitter lead 23 protrude (tothe right, or in the positive direction of X axis) from thecircuit-encapsulating portion 90. When, for example, thecircuit-encapsulating portion 90 is a rectangular prism, the first andsecond receiver leads 25 and 27 protrude from the surface of thecircuit-encapsulating portion 90 facing the surface from which the firstand second receiver leads 21 and 23 protrude. These leads may protrudeat any angles. The first and second emitter leads 25 and 27 extend inthe direction opposite to the first direction (the positive direction ofY axis). The first and second emitter leads 21 and 23, and the first andsecond receiver leads 25 and 27 are deformed to allow the light emitter10 and the light receiver 15 to face each other.

As shown in FIG. 16, the first emitter lead 21 includes a first emitterlead portion 202, a seventeenth emitter lead 205, an eighteenth emitterlead portion 266 d, a thirteenth bending portion 267, a nineteenthemitter lead portion 268 d, a fourteenth bending portion 269, a twentyemitter lead portion 270 d, a fifteenth bending portion 271, a twentyfirst emitter lead portion 272 d, a sixteenth bending portion 273, and atwenty second emitter lead portion 274 d. The shapes of the componentsfrom the eighteenth emitter lead portion 266 d to the twenty secondemitter lead portion 274 d are the same as the shapes of thecorresponding components shown in FIG. 7, which are the components fromthe eighth receiver lead portion 266 to the eleventh receiver leadportion 272 in the figure. The first emitter lead portion 202 has thesame shape as the first emitter lead portion 202 shown in FIG. 7. Thefirst emitter lead portion 202 differs from the conventional emitterlead described above greatly in the seventeenth emitter lead 205. Theseventeenth emitter lead 205 will now be described.

The seventeenth emitter lead 205 includes a fifth outer end 205 b, afifth inner end 205 a, and a fifth straight portion 205 c. The fifthinner end 205 a joins the first emitter lead extension 202 b and thefifth straight portion 204 g. The fifth inner end 205 a is bent. Thefifth straight portion 204 g extends outward in the optical axisdirection (X-axis direction) from the fifth inner end 205 a to the fifthouter end 205 b. The fifth outer end 205 b joins the fifth straightportion 205 c and the eighteenth emitter lead portion 266 d. The fifthouter end 205 b is bent. The eighteenth emitter lead portion 266 d isconnected to the seventeenth emitter lead 205. More specifically, theeighteenth emitter lead portion 266 d extends in the direction oppositeto the first direction (the positive direction of Y axis) from the fifthouter end 205 b to the thirteenth bending portion 267. Referring to FIG.16, the nineteenth emitter lead portion 268 d extends inward in theoptical axis direction (X-axis direction) from the thirteenth bendingportion 267. As shown in FIG. 16, the fifth inner end 205 a is locatedmore inward than the thirteenth bending portion 267 (corresponding to anouter end of the nineteenth emitter lead portion 268 d) in the opticalaxis direction (X-axis direction). In the optical axis direction, thefourteenth bending portion 269 is located more inward than the fifthouter end 205 b corresponding to an inner end of the nineteenth emitterlead portion 268 d. This positional relationship results from theeighteenth emitter lead portion 266 d arranged outward to allow thefirst bending portion B1 to have a sufficient margin for bending in thenineteenth emitter lead portion 268 d.

Referring to FIGS. 16 and 17, the second emitter lead 23 is located moreinward than the first emitter lead 21 in the optical axis direction(X-axis direction).

The second emitter lead 23 includes a sixth emitter lead 222, a twentythird emitter lead portion 244 d, a twenty fourth emitter lead portion246 d, a twenty fifth emitter lead portion 248 d, and a twenty sixthemitter lead portion 250 d. The shapes of the components from the twentythird emitter lead portion 244 d to the twenty sixth emitter leadportion 250 d are the same as the shapes of the corresponding componentsshown in FIG. 7, which are the components from the second receiver leadportion 244 to the fifth receiver lead portion 250 in the figure. Thesixth emitter lead 222 has the same shape as the sixth emitter lead 222shown in FIG. 7.

As shown in FIG. 16, the first receiver lead 24 includes a firstreceiver lead portion 242, a seventeenth receiver lead 245, aneighteenth receiver lead portion 226 d, a fifth bending portion 227, anineteenth receiver lead portion 228 d, a sixth bending portion 229, atwenty receiver lead portion 230 d, a seventh bending portion 231, atwenty first receiver lead 232 d, an eighth bending portion 233, and atwenty second receiver lead 234 d. The shapes of the components from theeighteenth receiver lead portion 226 d to the twenty second receiverlead 234 d are the same as the shapes of the corresponding componentsshown in FIG. 7, which are the components from the eighth emitter leadportion 226 to the twelfth emitter lead 234 in the figure. The firstreceiver lead 24 differs from the conventional receiver lead describedabove greatly in the seventeenth receiver lead 245. The seventeenthreceiver lead 245 will now be described.

The seventeenth receiver lead 245 includes a sixth outer end 245 b, asixth inner end 245 a, and a sixth straight portion 245 c. The sixthinner end 245 a joins the first emitter lead extension 242 b and thesixth straight portion 245 c. The sixth inner end 245 a is bent. Thesixth straight portion 245 c extends outward in the optical axisdirection (X-axis direction) from the sixth inner end 245 a to the sixthouter end 245 b. The sixth outer end 245 b joins the sixth straightportion 245 c and the eighteenth receiver lead portion 226 d. The sixthouter end 245 b is bent. The eighteenth receiver lead portion 226 d isconnected to the seventeenth receiver lead 245. More specifically, theeighteenth receiver lead portion 226 d extends in the direction oppositeto the first direction (the positive direction of Y axis) from the sixthouter end 245 b to the fifth bending portion 227. The nineteenthreceiver lead portion 228 d extends inward in the optical axis direction(X-axis direction) from the fifth bending portion 227. As shown in FIG.16, the sixth inner end 245 a is located more inward than the fifthbending portion 227 corresponding to an outer end the nineteenthreceiver lead portion 228 d in the optical axis direction (X-axisdirection). In the optical axis direction, the sixth bending portion 229corresponding to an inner end of the nineteenth receiver lead portion228 d is located more inward than the sixth outer end 245 b. Thispositional relationship results from the eighteenth receiver leadportion 226 d arranged outward to allow the second bending portion B2 tohave a sufficient margin for bending in the nineteenth receiver leadportion 228 d.

Referring to FIGS. 16 and 17, the second receiver lead 27 is locatedmore inward than the first receiver lead 25 in the optical axisdirection (X-axis direction). The second receiver lead 27 includes asixth receiver lead portion 262, a twenty third receiver lead portion204 d, a twenty fourth receiver lead portion 206 d, a twenty fifthreceiver lead portion 208 d, and a twenty sixth receiver lead portion210 d. The shapes of the components from the twenty third receiver leadportion 204 d to the twenty sixth receiver lead portion 210 d are thesame as the shapes of the corresponding components shown in FIG. 7,which are the components from the second emitter lead portion 204 to thefifth emitter lead portion 210 the eighth emitter lead portion 226 tothe twelfth emitter lead 234 in the figure. The sixth emitter leadportion 262 has the same shape as the sixth receiver lead portion 262shown in FIG. 7.

To shape the primary molded piece (sensor module 4 a) of the sensormodule 5 shown in FIG. 17 into the structure shown in FIG. 16 in whichthe light emitter 10 and the light receiver 15 face each other, thefirst emitter lead 21 and the second emitter lead 22 are bent along afirst bending line L1. The first receiver lead 25 and the secondreceiver lead 27 are bent along a second bending line L2. The firstbending line L1 is parallel to a second direction (Y-axis direction)that is perpendicular to the optical axis. The second bending line L2 isalso parallel to the second direction (Y-axis direction). Morespecifically, the nineteenth emitter lead portion 268 d includes thefirst bending portion B1, which is bent along the first bending line L1.The nineteenth receiver lead portion 228 d includes the second bendingportion B2, which is bent along the second bending line L2. The twentyfifth emitter lead portion 248 d includes a third bending portion B3,which is bent along the first bending line L1. The twenty fifth receiverlead portion 208 d includes a fourth bending portion B4, which is bentalong the second bending line L2.

As shown in FIG. 17, when the first emitter lead 21 and the secondemitter lead 23 are unfolded in a plane without bending along the firstbending line L1, the unfolded first emitter lead 21 and the unfoldedsecond emitter lead 23 extend across the first bending line L1. When thefirst receiver lead 25 and the second receiver lead 27 are unfolded in aplane without bending along the second bending line L2, the unfoldedfirst receiver lead 25 and the unfolded second receiver lead 27 extendacross the second bending line L2.

The first emitter lead portion 202, the sixth emitter lead 222, thefirst receiver lead portion 242, and the sixth receiver lead portion 262have the same shapes. To allow deburring after the process ofinjection-molding the circuit-encapsulating portion 90, the emitterleads 20 and 22 and the receiver leads 24 and 26 are arranged away fromthe circuit-encapsulating portion 90 by a distance of about 0.3 to 0.4mm. As shown in FIG. 16, the distance between the first emitter lead 21and the second emitter lead 23 is apparently larger than the distance D2in FIG. 6. The distance between the first emitter lead 21 and the secondemitter lead 23 is set to prevent contact between and achieve insulationbetween them. Likewise, the distance between the first receiver lead 25and the second receiver lead 27 is apparently larger than the distanceD4 in FIG. 6. The distance between the first receiver lead 25 and thesecond receiver lead 27 is set to prevent contact between and achieveinsulation between them. The first emitter lead 21, the second emitterlead 23, the first receiver lead 25, and the second receiver lead 27 arewide enough (e.g., not less than 0.5 mm) to have strength to bend andalso to support the light emitter 10 and the light receiver 15. To havesuch strength, the first emitter lead 21, the second emitter lead 23,the first receiver lead 25, and the second receiver lead 27 arepreferably formed from a copper alloy, gold, silver, or a nickel alloy.It is preferable that the first emitter lead 21, the second emitter lead23, the first receiver lead 25, and the second receiver lead 27 satisfythe conditions 1 to 4 described above. This structure achieves thesensor module 5 in which the emitter and receiver leads protrude fromthe side of the circuit-encapsulating portion 90.

The sensor module 4 shown in FIG. 7 changed to fit into an outerL-shaped type will now be described. Referring to FIG. 7, to change themodule to fit into an outer L-shaped type, the first emitter lead 20,the second emitter lead 22, the first receiver lead 24, and the secondreceiver lead 26 are bent not only along the bending lines L1 and L2 butalso along third and fourth bending lines L3 and L4. FIG. 18 is a sideview of the sensor module including emitter and receiver leads bent intoan L-shape as viewed in the optical axis direction. Referring to FIGS. 7and 18, the first emitter lead 20, the second emitter lead 22, the firstreceiver lead 24, and the second receiver lead 26 are bent along thefourth bending line L4 at an angle of 45 degrees with respect to thefirst plane (XY plane). The first emitter lead 20, the second emitterlead 22, the first receiver lead 24, and the second receiver lead 26include bending portions B6, B8, B10, and B12, which are bent along thefourth bending line L4. The first emitter lead 20, the second emitterlead 22, the first receiver lead 24, and the second receiver lead 26 arebent along the third bending line L3 at an angle of 45 degrees withrespect to the first emitter lead 20, the second emitter lead 22, thefirst receiver lead 24, and the second receiver lead 26, which are bentalong the fourth bending line L4. The first emitter lead 20, the secondemitter lead 22, the first receiver lead 24, and the second receiverlead 26 include bending portions B5, B7, B9, and B11, which are bentalong the third bending line L3. More specifically, the first emitterlead 20, the second emitter lead 22, the first receiver lead 24, and thesecond receiver lead 26 bent along the third bending line L3 areperpendicular to the first plane (XY plane). The sensor module bent intoan outer L-shaped type shown in FIG. 18 will be hereafter referred to asa sensor module 6.

A section including the bending portions B5 and B6, a section includingthe bending portions B7 and B8, a section including the bending portionsB9 and B10, and a section including the bending portions B11 and B12 areeach referred to as a direction changing section. In particular, asection including the bending portions B7 and B8 of the second emitterlead 22 is referred to as a first direction changing section. A sectionincluding the bending portions B11 and B12 of the second receiver lead26 is referred to as a second direction changing section.

The shape characteristics of the outer L-shaped type will now bedescribed focusing on the second emitter lead 22 and the second receiverlead 26. The sixth receiver lead portion 262 includes a sixth receiverlead protrusion 262 a, which extends from the circuit-encapsulatingportion 90 in the optical axis direction (X-axis direction), and extendson the first plane (XY plane) described above from thecircuit-encapsulating portion 90. The sixth receiver lead portion 262includes a sixth receiver extension 262 b, which extends on the firstplane in the direction perpendicular to the optical axis direction (thepositive direction of Y axis). This structure allows the second receiverlead 26 to protrude from the side surface of the circuit-encapsulatingportion 90, and thus the second receiver lead 26 can be bent along thebending line L4. The sixth receiver lead portion 262 may be referred toas a first receiver base lead, and the sixth receiver extension 262 bmay be referred to as a first receiver straight lead.

The eighth receiver lead portion 266 extends on a second plane (XZplane) perpendicular to the first plane in the direction perpendicularto the optical axis direction (the positive direction in Z axis). Theseventh receiver lead portion 264 joins the sixth receiver lead portion262 and the eighth receiver lead portion 266. The eighth receiver leadportion 266 may be referred to as a second receiver base lead, or as asecond receiver straight lead. The seventh receiver lead portion 264 maybe referred to as a receiver connection lead.

The sixth receiver extension 262 b includes a bending portion B12 thatis bent along the fourth bending line L4. More specifically, the sixthreceiver extension 262 b is bent. The eighth receiver lead portion 266includes a bending portion B11 that is bent along the third bending lineL3. The eighth receiver lead portion 266 is bent. The sixth receiverextension 262 b and the eighth receiver lead portion 266 are bothlinear. Such lead portions are bent and thus allow easy bending.Referring to FIG. 18, the second receiver lead 26 is bent in the sixthreceiver extension 262 b at an angle of 45 degrees, and bent in theeighth receiver lead portion 266 at an angle of 45 degrees. The totalangle by which the sixth receiver extension 262 b is bent and the eighthreceiver lead portion 266 is bent is 90 degrees. The second receiverlead 26 may not be bent at two positions each at an angle of 45 degreesas shown in FIG. 18, but may be bent at three or more points in a mannerto achieve the total bending angle of 90 degrees. Alternatively, thesecond receiver lead 26 may be bent in a curve so that the unbentsurface and the bent surface form an angle of 90 degrees.

The second receiver lead 26 extends from its third base S3, which is onthe surface of the circuit-encapsulating portion 90, to its fourth baseS4, which is on the surface of the light emitter 10. The second receiverlead 26 includes a second direction changing section between the thirdbase S3 and the fourth base S4. The second direction changing sectionchanges the direction in which the second receiver lead 26 extends fromthe first plane (XY plane) to the direction perpendicular to the firstplane. The second receiver lead 26 is bent at multiple points betweenthe third base S3 and the fourth base S4. Referring to FIG. 18, thelength of the second receiver lead 26 from the third base S3 and thesecond direction changing section to the fourth base S4 as viewed in theoptical axis direction (X-axis direction) is defined by the total of astraight-line distance D31 from the third base S3 to the seconddirection changing section (bending portion B12) viewed in the opticalaxis direction (X-axis direction), a straight-line distance D32 from thesecond direction changing section (bending portion B11) to the fourthbase S4 viewed in the optical axis direction, and a straight-linedistance D33 between one end of the second direction changing section incontact with a portion of the second receiver lead 26 extending from thethird base S3 and the other end of the second direction changing sectionin contact with a portion of the second receiver lead 26 extending tothe fourth base S4 viewed in the optical axis direction. The length ofthe second receiver lead 26 extending from the third base S3 and thesecond direction changing section to the fourth base S4 as viewed in theoptical axis direction is smaller than the length (D41+D42) of anL-shaped second virtual lead 26 v (indicted by a chain double-dashedline in FIG. 18) that is bent at one point by 90 degrees between thethird base S3 and the fourth base S4 viewed in the optical axisdirection.

Referring to FIG. 7, the sixth emitter lead 222 includes a sixth emitterlead protrusion 222 a, which extends from the circuit-encapsulatingportion 90 in the optical axis direction (X-axis direction), and extendson the first plane (XY plane) from the circuit-encapsulating portion 90.The sixth emitter lead 222 includes a sixth emitter lead extension 222b, which extends on the first plane in the direction perpendicular tothe optical axis direction (the positive direction of Y axis). Thisstructure allows the second emitter lead 22 to protrude from the sidesurface of the circuit-encapsulating portion 90, and thus the secondemitter lead 22 can be bent along the bending line L4. The sixth emitterlead 222 may be referred to as a first emitter base lead, and the sixthemitter lead extension 222 b may be referred to as a first emitterstraight lead.

The eighth emitter lead portion 226 extends on a second plane (XZ plane)perpendicular to the first plane in the direction perpendicular to theoptical axis direction (the positive direction in Z axis). The seventhemitter lead portion 224 connects the sixth emitter lead 222 and theeighth emitter lead portion 226. The eighth emitter lead portion 226 maybe referred to as a second emitter base lead, or as a second emitterstraight lead. The seventh emitter lead portion 224 may be referred toas an emitter connection lead.

The sixth emitter lead extension 222 b includes a bending portion B8that is bent along the fourth bending line L4. More specifically, thesixth emitter lead extension 222 b is bent. The eighth emitter leadportion 226 includes a bending portion B7 that is bent along the thirdbending line L3. The eighth emitter lead portion 226 is bent. The sixthemitter lead extension 222 b and the eighth emitter lead portion 226 areboth linear. Such lead portions are bent and thus allow easy bending.The second emitter lead 22 is bent in the sixth emitter lead extension222 b at an angle of 45 degrees, and bent in the eighth emitter leadportion 226 at an angle of 45 degrees. The total angle by which thesixth emitter lead extension 222 b is bent and the eighth emitter leadportion 226 is bent is 90 degrees. The second emitter lead 22 may not bebent at two points each at an angle of 45 degrees as shown in FIG. 18,but may be bent at three or more points in a manner to achieve the totalbending angle of 90 degrees. Alternatively, the second emitter lead 22may be bent in a curve so that the unbent surface and the bent surfaceform an angle of 90 degrees.

The second emitter lead 22 extends from its first base 51, which is onthe surface of the circuit-encapsulating portion 90, to its second baseS2 (refer to FIG. 7), which is on the surface of the light emitter 10.The second emitter lead 22 includes a second direction changing sectionbetween the first base 51 and the second base S2. The second directionchanging direction changes the direction in which the second emitterlead 22 extends from the first plane (XY plane) to the directionperpendicular to the first plane. The second emitter lead 22 is bent atmultiple points between the first base and the second base. The lengthof the second emitter lead 22 from the first base 51 and the firstdirection changing section to the second base S2 as viewed in theoptical axis direction (X-axis direction) is defined by the total of astraight-line distance from the first base 51 to the first directionchanging section (bending portion B6) viewed in the optical axisdirection (X-axis direction), a straight-line distance from the firstdirection changing section (bending portion B6) to the second base S2viewed in the optical axis direction, and a straight-line distancebetween one end of the first direction changing section in contact witha portion of the second emitter lead 22 extending from the first base S1and the other end of the first direction changing section in contactwith a portion of the second emitter lead 22 extending to the secondbase S2 viewed in the optical axis direction. The length of the secondemitter lead 22 extending from the first base S1 and the first directionchanging section to the second base S2 as viewed in the optical axisdirection is smaller than the length (D41+D42) of an L-shaped firstvirtual lead bent at one point by 90 degrees between the first base S1and the second base S2 viewed in the optical axis direction. This allowsthe single sensor module 4 to be bent to fit into a flat (straight) typeor an outer L-shaped type. FIG. 18 is a left side view of the sensormodule, and does not show the second emitter lead 22. As describedabove, the second emitter lead 22 is symmetric to the second receiverlead 26 with respect to the plane C1 (refer to FIG. 6). Thus, the secondemitter lead 22 is bent in the same manner as shown in FIG. 18. Further,the first virtual lead has the same shape as the second virtual lead 26v.

In this manner, bending the first emitter lead 20, the second emitterlead 22, the first receiver lead 24, and the second receiver lead 26enables the free setting of the Z-axis distance between the lightemitter 10 and the circuit-encapsulating portion 90, and the Z-axisdistance between the light receiver 15 and the circuit-encapsulatingportion 90. This increases the degree of freedom in designing the outershape of the photosensor 1 (optical axis Ax).

Case for Sensor Module

A case for encasing the sensor module 5 will now be described. When thesensor module 5 is placed in the case 60, the subcase 80 is also used.The subcase 80 guides the light emitter 10 and the light receiver 15when the sensor module 5 is placed into the case 60, and prevents thefirst emitter lead 20, the second emitter lead 22, the first receiverlead 24, and the second receiver lead 26 from coming in contact with theinner wall of the case 60 and being deformed. FIG. 19A is a front viewof the subcase 80. FIG. 19B is a bottom view of the subcase 80. FIG. 19Cis a left side view of the subcase 80. FIG. 19D is a right side view ofthe subcase 80.

As shown in FIG. 4, the case 60 accommodates the light emitter 10, thefirst emitter lead 20, the second emitter lead 22, the light receiver15, the first receiver lead 24, and the second receiver lead 26 of thesensor module 5, and the subcase 80. The case body 61 accommodates thecircuit-encapsulating portion 90. The emitter case section 62accommodates the light emitter 10, the first emitter lead 20, and thesecond emitter lead 22. The receiver case section 63 accommodates thelight receiver 15, the first receiver lead 24, and the second receiverlead 26. The circuit-encapsulating portion 90 is supported on the baseplate 98. The base plate 98 is engaged with a part of the case body 61and is fixed.

The subcase 80 includes a first top plate 81, a second top plate 83, afirst wall portion 82, a second wall portion 84, and a base plateportion 85. The subcase 80 is formed from a material that allows lightwith a specific frequency (e.g., infrared light) emitted from the lightemitting element 11 to pass through. The first wall portion 82 extendsperpendicularly from one end of the base plate portion 85. The secondwall portion 84 extends perpendicularly from the other end of the baseplate portion 85 and in the same direction as the direction in which thefirst wall portion 82 extends. In other words, the base plate portion 85joins the first wall portion 82 and the second wall portion 84. Thedirection in which the first wall portion 82 and the second wall portion84 from the base plate portion 85 is referred to as a third direction.The first top plate 81 extends in a first outward direction from the topend of the first wall portion 82 in the third direction. The top end ofthe first wall portion 82 in the third direction is located opposite tothe basal end of the first wall portion 82 in the third direction, whichis in contact with the base plate portion 85. The first outwarddirection refers to a direction from the basal end of the second wallportion 84 toward the basal end of the first wall portion 82 in thethird direction. The second top plate 83 extends in a second outwarddirection from the top end of the second wall portion 84 opposite to thebasal end of the second wall portion 84 in the third direction, which isin contact with the base plate portion 85. The second outward directionrefers to a direction from the basal end of the first wall portion 82toward the basal end of the second wall portion 84. The first top plate81, the second top plate 83, and the base plate portion 85 are parallelto each other. The first wall portion 82 is parallel to the second wallportion 84.

As shown in FIGS. 4 and 5, the first top plate 81 and the first wallportion 82 are placed into the emitter case section 62. The second topplate 83 and the second wall portion 84 are placed into the receivercase section 63. Referring to FIG. 5, the first wall portion 82 comes incontact with a first inner wall surface 64 a of the emitter case section62 facing the light emitter 10. The second wall portion 84 comes incontact with a second inner wall surface 65 a of the receiver casesection 63 facing the light receiver 15. Referring to FIG. 4, an end 81a of the first top plate 81 facing in the direction opposite to thedirection in which light from the light emitter 10 travels (the negativedirection of X axis) comes in contact with the third inner wall surface64 b of the emitter case section 62 facing the first inner wall surface64 a. An end 83 a of the second top plate 83 facing in the direction inwhich the light travels (the positive direction of X axis) comes incontact with the fourth inner wall surface 65 b of the receiver casesection 63 facing the second inner wall surface 65 a. The end 81 a andthe end 83 a may not be flat, but may have protrusions or may be sharp.The third inner wall surface 64 b extends from the inside of the emittercase section 62 to the basal end of the case body 61. The fourth innerwall surface 65 b extends from the inside of the receiver case section63 to the basal end of the case body 61. This structure allows thesubcase 80 to be placed into the case 60 while allowing the subcase 80to slide on the first inner wall surface 64 a, the second inner wallsurface 65 a, the third inner wall surface 64 b, and the fourth innerwall surface 65 b of the case 60. This achieves smooth placement of thesubcase 80 into the case 60. This structure also prevents the first wallportion 82 and the second wall portion 84 from touching the inner wallsurface of the case 60 and being deformed when the subcase 80 is placedinto the case 60. The subcase 80 and the case 60 with the structuresdescribed above allow the subcase 80 to be easily placed by using amachine.

As shown in FIG. 4, the first top plate 81 faces the fifth inner wallsurface 64 c of the emitter case section 62 facing the case body 61. Inother words, the first top plate 81 faces the case body 61. Further, thesecond top plate 83 faces the sixth inner wall surface 65 c of thereceiver case section 63 facing the case body 61. In other words, thesecond top plate 83 faces the case body 61. When the subcase 80 isplaced into the case 60 by using a machine, the machine may detect apressure generated when the first top plate 81 comes in contact with thefifth inner wall surface 64 c and the second top plate 83 comes incontact with the sixth inner wall surface 65 c. This allows the machineto detect that the subcase has been placed completely, and allows easierplacement of the subcase by using a machine.

Referring to FIG. 19B and FIG. 5, the first wall portion 82 includes afirst wall surface 82 a, a second wall surface 82 b, a first groove 82c, and a first protrusion 82 d. The first wall surface 82 a comes incontact with the first inner wall surface 64 a. The second wall surface82 b is opposite to the first wall surface 82 a. The first groove 82 cis arranged on the second wall surface 82 b, and comes in contact with apart of the emitter lens 14. The first protrusion 82 d is arranged onthe first wall surface 82 a, and protrudes in the direction toward thesecond wall portion 84. The first protrusion 82 d protrudes inconformance with the recess of the first groove 82 c.

Referring to FIG. 19B and FIG. 5, the second wall portion 84 includes athird wall surface 84 a, a fourth wall surface 84 b, a second groove 84c, and a second protrusion 84 d. The third wall surface 84 a comes incontact with the second inner wall surface 65 a. The fourth wall surface84 b is opposite to the third wall surface 84 a. The second groove 84 cis arranged on the fourth wall surface 84 b, and comes in contact with apart of the emitter lens 14. The second protrusion 84 d is arranged onthe third wall surface 84 a, and protrudes in the direction toward thefirst wall portion 82. The second protrusion 84 d protrudes inconformance with the recess of the second groove 84 c.

When the sensor module 5 is placed in the case 60 encasing the subcase80, the emitter lens 14 slides on the first groove 82 c, and thereceiver lens 19 slides on the second groove 84 c. Mechanically placingthe sensor module 5 can allow the optical axis of the light emitter 10and the optical axis of the light receiver 15 to be aligned with eachother. The positions of the light emitter 10 and the light receiver 15are fixed on the first groove 82 c and the second groove 84 c. Thisstructure prevents large misalignment between the optical axes of theemitter lens 14 and the receiver lens 19 when, for example, thephotosensor 1 receives vibrations.

As shown in FIG. 5, the first protrusion 82 d is engaged with theemitter slit 66, and the second protrusion 84 d is engaged with thereceiver slit 67. The emitter slit 66 and the receiver slit 67 eachfunction as a guide in placing the subcase 80 into the case 60. Thisfurther facilitates the operation of placing the subcase 8 into the case60.

As shown in FIGS. 4 and 5, the subcase 80 includes the first top plate81, the second top plate 83, the first wall portion 82, and the secondwall portion 84 covering the top of the light emitter 10 and the lightreceiver 15, and covering the right side and the upper side of theemitter lens 14 of the light emitter 10 and the left side and the upperside of the receiver lens 19 of the light receiver 15 from which lightis emitted and received. This structure reduces static electricity thatcan be generated around the emitter case section 62 and the receivercase section 63 affecting the light emitting element 11, the receiverelement 16, the first emitter lead 20, the second emitter lead 22, thefirst receiver lead 24, and the second receiver lead 26.

The case for encasing an outer L-shaped type also uses the subcase 80.FIG. 20 is a front view of an outer L-shaped photosensor 2. FIG. 21 is atop view of the outer L-shaped photosensor 2. FIG. 22 is an explodedperspective view of the outer L-shaped photosensor 2. In FIGS. 20 to 22,the components that are the same as the components shown in FIGS. 1 to 3are given the same reference numerals as those components and will notbe described.

As shown in FIGS. 20 to 22, the photosensor 2 differs from thephotosensor 1 in the shape of its case 60 a. The case 60 a includes anemitter case section 62 and a receiver case section 63 that are the sameas in the case 60. The photosensor 2 thus has all the characteristicsdescribed above associated with the subcase 80, the emitter case section62, and the receiver case section 63. The characteristics of the caseassociated with the subcase 80, the emitter case section 62, and thereceiver case section 63 will not be described.

The case 60 a includes a case body 61 a with a shape different from thecase body 61. As shown in FIG. 21, the case body 60 a includes anindicator lamp window 68 as an opening in the front. The indicator lampwindow 68 allows visual checking of an operation indicator 92. The casebody 60 a has mounting holes 69 a and 69 b in the directionperpendicular to the direction in which the emitter and receiver slitsface each other (Y-axis direction in FIG. 21). The holes 69 a and 69 bare formed through the case 60. The photosensor 2 includes connectingterminals 50, which are a part of the sensor module 5. The connectingterminals 50 protrude frontward from the case 60 a. As shown in FIG. 22,the subcase 80 and the sensor module 6 are placed into the case 60 a inthis order. A base plate 98 a for supporting the circuit-encapsulatingportion 90 is then attached to the bottom of the case 60 a.

FIG. 23 is a cross-sectional view of the photosensor 2 taken along lineXXIII-XXIII of FIG. 21. With reference to FIG. 23, the characteristicsof the inside of the case body 61 a will be described. First, the thirdinner wall surface 64 b extends from the inside of the emitter casesection 62 to the basal end of the case body 61 a. The fourth inner wallsurface 65 b extends from the inside of the receiver case section 63 tothe basal end of the case body 61 a. The circuit-encapsulating portion90 is supported by the base plate 98 a. The circuit-encapsulatingportion 90 comes in contact with the base plate portion 85 of thesubcase 80 and supports the base plate portion 85.

Although the embodiment of the present invention has been described, theinvention should not be limited to the above embodiment. Variousmodifications are possible without departing from the scope and spiritof the invention.

The position of the light emitter 10 and the position of the lightreceiver 15 may be reversed. When the positions of the light emitter 10and the light receiver 15 are reversed, the position of the firstemitter lead 20 and the position of the first receiver lead 24 arereversed, and the position of the second emitter lead 22 and theposition of the second receiver lead 26 are reversed in accordance withthe positions of the light emitter 10 and the light receiver 15. Theposition of the emitter case section 62 and the position of the receivercase section 63 are also reversed accordingly.

The emitter lens 14 and the receiver lens 19 may not be circular. Forexample, the emitter lens 14 and the receiver lens 19 may be oval.

The number of connecting terminals may not be four. The sensor modules4, 5, and 6 may include more than four or less than four connectingterminals. The sensor modules 4, 5, and 6 may not include the operationindicator 92.

INDUSTRIAL APPLICABILITY

The photosensor of the present invention includes a sensor module inwhich emitter and receiver leads protrude from a circuit-encapsulatingportion in a direction intersecting with a direction in which externalconnecting terminals extend.

REFERENCE SIGNS LIST

-   1, 2 photosensor-   10 light emitter-   15 light receiver-   90 circuit-encapsulating portion-   50 connecting terminal-   20 first emitter lead-   22 second emitter lead-   24 first receiver lead-   26 second receiver lead-   L1 first bending line-   L2 second bending line-   202 first emitter lead-   204 second emitter lead-   206 third emitter lead-   208 fourth emitter lead-   B1 first bending portion-   B2 second bending portion-   224 seventh emitter lead (inclined light emitting portion)-   264 seventh receiver lead (inclined light receiving portion)

1. A photosensor, comprising: a light emitter; a light receiverconfigured to receive light from the light emitter and output a lightreceiving signal; a circuit-encapsulating portion encapsulating anintegrated circuit that processes the light receiving signal; aconnecting terminal protruding from the circuit-encapsulating portion,the connecting terminal being configured to connect to an externalterminal; a first emitter lead and a second emitter lead configured toconnect the light emitter and the circuit-encapsulating portion, theemitter leads being flat plates; and a first receiver lead and a secondreceiver lead configured to connect the light receiver and thecircuit-encapsulating portion, the receiver leads being flat plates,wherein when a direction in which the connecting terminal extends is afirst direction, and a plane parallel to the first direction is a firstplane, the first emitter lead and the second emitter lead protrude fromthe circuit-encapsulating portion in a direction parallel to a firstplane and intersecting with the first direction, and extend in adirection opposite to the first direction, the first receiver lead andthe second receiver lead protrude from the circuit-encapsulating portionin a direction parallel to the first plane and intersecting with thefirst direction and opposite to a direction in which the first emitterlead and the second emitter lead protrude, and extend in the directionopposite to the first direction, and the first emitter lead and thesecond emitter lead, and the first receiver lead and the second receiverlead are deformed to allow the light receiver and the light emitter toface each other.
 2. The photosensor according to claim 1, wherein thefirst emitter lead and the second emitter lead are bent along a firstbending line that is parallel to a second direction perpendicular to anoptical axis of the light, and the first receiver lead and the secondreceiver lead are bent along a second bending line that is parallel tothe second direction.
 3. The photosensor according to claim 1, whereinwhen the first emitter lead and the second emitter lead are unfolded ina plane without bending along the first bending line, the unfolded firstemitter lead and the unfolded second emitter lead extend across thefirst bending line, and when the first receiver lead and the secondreceiver lead are unfolded in a plane without bending along the secondbending line, the unfolded first receiver lead and the unfolded secondreceiver lead extend across the second bending line.
 4. The photosensoraccording to claim 1, wherein the first emitter lead includes a firstemitter lead portion that protrudes from the circuit-encapsulatingportion in a direction parallel to the first plane and intersecting withthe first direction, and extends in a direction opposite to the firstdirection; a second emitter lead portion that extends from the firstemitter lead portion in one of an inward direction or an outwarddirection along an optical axis of the light; a third emitter leadportion connected to the second emitter lead portion; and a fourthemitter lead portion that extends from the third emitter lead portion inthe other one of the inward direction or the outward direction along theoptical axis, the fourth emitter lead portion includes a first bendingportion that is bent along the first bending line, the first receiverlead includes a first receiver lead portion that protrudes from thecircuit-encapsulating portion in a direction parallel to the first planeand intersecting with the first direction, and extends in a directionopposite to a direction in which the first emitter lead and the secondemitter lead protrude, a second receiver lead portion that extends fromthe first receiver lead portion in one of an inward direction or anoutward direction along the optical axis; a third receiver lead portionconnected to the second receiver lead portion; and a fourth receiverlead portion that extends from the third receiver lead portion in theother one of the inward direction or the outward direction, and thefourth receiver lead portion includes a second bending portion bentalong the second bending line.
 5. The photosensor according to claim 4,wherein an inner end of the second emitter lead portion is located moreinward than an outer end of the fourth emitter lead portion in adirection along the optical axis, an inner end of the fourth emitterlead portion is located more inward than an outer end of the secondemitter lead portion in the optical axis direction, an inner end of thesecond receiver lead portion is located more inward than an outer end ofthe fourth receiver lead portion in the optical axis direction, and aninner end of the fourth receiver lead portion is located more inwardthan an outer end of the second receiver lead portion in the opticalaxis direction.
 6. The photosensor according to claim 4 wherein thesecond emitter lead portion extends inward from the first emitter leadportion in a direction along the optical axis, the fourth emitter leadportion extends outward from the third emitter lead portion in theoptical axis direction, the second receiver lead portion extends inwardfrom the first receiver lead portion in the optical axis direction, andthe fourth receiver lead portion extends outward from the third receiverlead portion in the optical axis direction.
 7. The photosensor accordingto claim 6, wherein the second emitter lead is located more inward thanthe first emitter lead in the optical axis direction, the secondreceiver lead is located more inward than the first receiver lead in theoptical axis direction, a distance between the second emitter lead andthe third emitter lead portion in the optical axis direction is smallerthan a distance between the second emitter lead and the first emitterlead portion in the optical axis direction, and a distance between thesecond receiver lead and the third receiver lead portion in the opticalaxis direction is smaller than a distance between the second receiverlead and the first receiver lead portion in the optical axis direction.8. The photosensor according to claim 7, wherein the second emitter leadincludes an inclined light emitting portion that is inclined to increasea distance thereof to the first emitter lead portion in the optical axisdirection, and the second receiver lead includes an inclined lightreceiving portion that is inclined to increase a distance thereof to thefirst receiver lead portion in the optical axis direction.
 9. Thephotosensor according to claim 5, wherein the second emitter leadportion extends inward from the first emitter lead portion in adirection along the optical axis, the fourth emitter lead portionextends outward from the third emitter lead portion in the optical axisdirection, the second receiver lead portion extends inward from thefirst receiver lead portion in the optical axis direction, and thefourth receiver lead portion extends outward from the third receiverlead portion in the optical axis direction.